GPU Custom Resolution & Refresh Rate with CRU: How to Add Custom Modes Safely, Bandwidth Limits & How to Undo It

2026-10-24 ｜ GPU Repair ｜ About 34 minutes ｜ HK GPU Fix Editorial Team

重點摘要

Custom Resolution Utility lets Windows offer display modes your monitor's EDID omitted, but it cannot create capability your panel, cable, port, or graphics card lacks. This guide explains how EDID overrides work, puts the full recovery ladder first, then walks through adding a mode safely, testing it, and removing it if anything goes wrong.

Read This First: Prepare Before You Edit Anything

Most guides about Custom Resolution Utility, known as CRU, begin with how to add a mode. This guide begins with how to undo one, because the order matters. A bad custom mode can leave the screen black, and a reader who first learns about the recovery tools while staring at a black screen has been failed by the article. Read this section completely, prepare the tools it names, and only then move on to the how-to.

Step Zero: Export the Original EDID

Before editing anything in CRU, export the original EDID for the display. The export is the baseline: it records what the display reported before any override existed. Keep it somewhere it can be found again, and do not overwrite it with an edited version. If an override ever needs to be reconstructed or compared against the original, this export is the reference. Editing without a baseline is guessing without a way back.

Step Zero, Continued: Know Where the Recovery Tools Live

CRU is a portable Windows utility: extract the folder and run CRU.exe, with no installation step. In the same folder live two small tools that matter more than CRU itself when something goes wrong. The first is restart64.exe on a 64-bit system, or restart.exe on a 32-bit system, which restarts the graphics driver so new modes appear without restarting Windows. The second is reset-all.exe, which removes all EDID overrides. Know the folder path before editing, so the tools can be found without seeing the screen. A recovery tool whose location is unknown during a black screen is not a recovery tool.

Where possible, keep a second display or a known-good connection available for recovery. A second screen turns a black-screen emergency into a routine fix, because CRU can be opened and the override removed on the working display. Not every reader has a second display, and this guide does not assume one, but where one exists, keep it connected during the first custom-mode test.

The Recovery Ladder: What to Do When the Screen Goes Black or Says "Out of Range"

Present this ladder as a sequence, not as a menu of options. Work down it in order, and stop at the first step that restores a visible screen.

1. Wait, Then Use CRU Recovery Mode

After a driver restart, if the display does not return within about 15 seconds, press F8 for recovery mode, as CRU's own documentation describes. Recovery mode temporarily unloads all EDID overrides without deleting them. The screen should return, showing the display's original behaviour. Once the screen is visible and the faulty mode has been corrected in CRU, restart the driver again to reload the changes. Recovery mode is a pause, not a deletion: it gives the reader a visible screen from which to fix the problem properly.

2. Remove the Single Bad Override

In CRU, use the "Delete" button at the top to delete the override for that display from the registry, then reboot. This returns that display to its original EDID, while leaving other displays' overrides untouched. Use this step when one display is the problem and the others are fine.

3. Remove All Overrides

Run reset-all.exe from the CRU folder, then reboot. This resets all displays to their defaults. Use this step when the faulty display cannot be identified confidently, or when several overrides are suspect. It is a broader reset than step 2, and it is still fully reversible in the sense that overrides can be recreated later from the exported original EDID and from notes about what was changed.

4. Safe Mode as the Fallback When Nothing Is Visible

If the bad mode applies at login and the screen stays black, boot to safe mode. The Windows recovery path is Troubleshoot, then Advanced options, then Startup Settings, then Restart, then Safe Mode. CRU's documentation also notes that forcing two interrupted boots can bring up the recovery options. Safe mode bypasses custom graphics settings, which is why it works here: the bad override does not determine the display in safe mode. In safe mode, run reset-all.exe and reboot. CRU's documentation states that reset-all can be done in safe mode if necessary.

5. If the Driver Is Disabled After a Crash During Restart

If the driver crashes during a restart and is disabled after reboot, run restart.exe again to re-enable the driver. This is the documented fix for this specific state. Do not reinstall the driver as the first step. Reinstallation is a longer, more disruptive action for a problem whose documented remedy is a single tool run.

A Warning About Order

Do not begin recovery by editing the registry by hand. CRU's own Delete button and reset-all.exe are the supported path, and they exist precisely so that readers do not need to hunt through registry keys while a screen is black. Hand registry editing as a first recovery step risks a second fault on top of the first, with no visible screen on which to notice it. Use the tools the utility provides, in the order above.

One More Distinction Before Proceeding

A black screen immediately after applying a CRU mode is an override or timing fault first, and this section is the response to it. It is not, at this stage, a load crash of the kind that occurs under rendering, 3D, or AI workloads, which has its own diagnostic path. Treating a CRU black screen as a load crash leads to the wrong fixes: driver reinstallation, hardware suspicion, and wasted time. Treat it as an override fault, work the ladder above, and only if the screen remains black after the overrides are removed should the diagnosis broaden.

What CRU Actually Does: The EDID Override, Explained

EDID Is the Display's Capability Card

EDID stands for Extended Display Identification Data. It is a standard data block stored in the display that tells the connected computer what the display can handle: the manufacturer, the preferred and native resolution and refresh rate, other accepted resolutions and refresh rates, colour characteristics, and related capability data. The computer reads EDID on connection, through the Display Data Channel, and offers only modes consistent with it.

That mechanism explains two everyday observations. A mode the panel supports but the EDID omits may simply not appear in Windows, because Windows has never been told the display accepts it. Conversely, a mode the EDID lists but the chain cannot deliver may appear and then fail, because the capability card is a claim, and the cable, port, GPU output, and panel must still deliver on it. EDID is the beginning of the negotiation, not the end of it.

CRU Writes a Windows Override, Not Monitor Firmware

CRU, Custom Resolution Utility by ToastyX, edits the EDID information Windows uses for a display and saves the override in the registry. The CRU interface marks a modified display with an asterisk. CRU does not flash the monitor. It does not change the panel. It does not change the cable or the port. The monitor itself is unchanged.

Deleting the override, using CRU's "Delete" button for that display and then rebooting, or running reset-all.exe and then rebooting, returns Windows to the display's original EDID. That is why the recovery ladder above works: the change lives in Windows configuration data, and Windows configuration data can be removed.

But "reversible" does not mean "harmless while the bad mode is active". A bad mode can leave the screen black until the override is removed, and a reader without the recovery ladder in hand is stuck at exactly that moment. Reversibility is a property of the system after recovery. It is not comfort during the black screen. Keep that distinction in mind throughout the how-to below.

CRU Adds Monitor Resolutions, Not Scaled Resolutions

This distinction is easy to miss and expensive to misunderstand. CRU adds monitor resolutions: modes that the monitor itself is asked to display. Lower resolutions can be scaled up to native resolution by enabling GPU scaling in the driver control panel. Higher resolutions will not be scaled down by the GPU. A higher resolution only works if the monitor can actually handle it.

The honest consequence follows. A CRU mode above a panel's native resolution, described as though the panel were now showing that higher resolution in full detail, is a misdescription. At best, the graphics card renders at the higher resolution and the chain downscales the picture, or the panel rejects the mode outright. The article must say which is happening on the reader's setup, not assume it. A mode that is listed is not a mode that is displayed natively, and a mode that is displayed is not necessarily displayed at the resolution the reader believes.

Where to Put What: Detailed, Standard, and Extension Blocks

CRU organises its editing into three places, and choosing the right one is most of the skill. The table below is the decision guide. The sections after it explain each place in turn.

Detailed Resolutions: The Preferred Way to Add a Mode

Detailed resolutions carry a full timing definition: active pixels, blanking and sync timing, pixel clock, and refresh rate. They are the preferred way to add a custom resolution, because they define exactly what the display is being asked to do.

Two rules govern detailed resolutions. First, the first detailed resolution is treated as the preferred, or native, resolution, and at least one detailed resolution should exist to define the native resolution. Do not delete all detailed resolutions and leave the display without a defined native mode. Second, other resolutions can be removed if not needed, because the graphics driver automatically adds some common lower resolutions as scaled resolutions. Removing clutter is safe; removing the native definition is not.

For the common case, adding a custom refresh rate at the native resolution, the detailed resolution entry at that resolution is the place to work. Change the refresh rate there, keep the resolution at native, and let the timing preset fill the timing values unless the reader genuinely understands manual timing.

Standard Resolutions: The Coarse List

Standard resolutions are a simpler list of resolution entries without full timing detail. They are useful for adding ordinary modes quickly, where the reader does not need a custom refresh rate or a custom timing definition.

Their limits matter. NVIDIA does not support more than 8 standard resolutions in the base list. Empty detailed-resolution slots and extension blocks extend this capacity, per CRU forum guidance. A reader who needs more than a handful of ordinary modes should therefore use detailed slots or an extension block rather than fighting the standard list's ceiling. Standard resolutions are a convenience for common modes, not the tool for a custom refresh rate at a specific resolution. For that, use a detailed resolution.

Extension Blocks: The Highest-Risk Area

The CTA-861 extension block is where additional modes, range limits, and capability data live, including variable refresh rate and FreeSync ranges where the display reports them. More detailed resolutions can be added using extension blocks. DisplayID extension blocks raise the ceiling for very large modes.

Editing an extension block is editing capability data, not just adding a mode name. A wrong range limit or a wrong variable refresh rate range can make a mode appear that the panel cannot hold, or hide a mode that should work. The discipline here is strict: export the original EDID first, change one thing, test it, and only then continue. A reader who edits several extension blocks at once and then faces a black screen cannot tell which edit caused it, and must remove everything and start again. One change, one test, is slower and is the only method that preserves diagnosis.

The Hard Limits Inside CRU

CRU's own documentation states exact format limits, and they must be stated exactly, as format limits, not as panel limits. EDID detailed resolutions are limited to 4095 by 4095 pixels and a 655.35 MHz pixel clock. If a value turns red in CRU, it is invalid or out of limits. Use a DisplayID extension block to add resolutions with higher limits.

Those numbers describe the EDID format inside CRU. They do not describe what a panel can display. A mode within these limits can still fail for bandwidth or panel reasons, and the next section explains why. Conversely, a mode beyond these limits is not a challenge to force through a different timing preset; it is a signal to use a DisplayID block or to lower the mode. Red values are not warnings that can be ignored. Red means invalid or out of limits, and submitting a red value invites exactly the black screen this guide's recovery ladder exists to fix.

The Central Warning: CRU Cannot Create Bandwidth, a Port, or a Panel

CRU edits what Windows believes the display can do. It does not change what the display, cable, port, or GPU output can deliver. The chain is only as capable as its weakest link, and no EDID edit strengthens a weak link. This is the article's central warning, and every other section is subordinate to it.

The Panel

A mode above the panel's native resolution, or above its supported refresh rate at that resolution, will not become real by being listed. Higher resolutions only work if the monitor can handle them, as CRU's documentation states plainly. A panel asked for a mode it cannot show typically shows an "out of range" message, a black screen, or a scaled or letterboxed picture. None of those is a sharper image. They are the panel's way of saying the request exceeds its capability.

The Cable and the Port

The mode's pixel clock and bandwidth must fit the cable and the ports at both ends. Forum diagnosis consistently shows the same pattern: a mode that exceeds a single-link or older-port limit fails with a bandwidth error or simply does not appear, and the fix is a direct connection on a capable port and cable, not a bolder override. A single-link path caps at 1080p60-class bandwidth, and an HDMI-to-DVI path is limited by the weaker side. Those are examples of the principle, not a bandwidth table; full bandwidth arithmetic for high-resolution, high-refresh modes belongs to the companion discussion of display bandwidth, and cable certification, labelling, and how to tell a certified cable from an uncertified one belong to the companion discussion of cable certification. This article states the principle and routes the detail there.

One practical line belongs here, and only one line. If a CRU mode fails, test with a known-good cable on the shortest direct path before blaming the override. A failing cable in the middle of the chain produces symptoms that look exactly like a failing override, and no amount of CRU editing fixes a cable.

The GPU Output

The GPU's display engine and driver also have mode limits. A mode CRU accepts can still be rejected by the driver, or it can appear but flicker or drop. There are three signals, in order, and all three mean the same thing. A red value in CRU is the first signal. A driver rejection is the second. A black screen is the third. All three mean "stop and lower the mode", not "try a different timing preset to force it". Forcing past a driver rejection is not persistence; it is the path to a black screen that the recovery ladder must then undo.

Scaling Versus Native, Restated Honestly

CRU adds monitor resolutions, not scaled resolutions. GPU scaling can scale a lower resolution up to native. It will not scale a higher resolution down to fit a panel. A reader who believes a CRU mode above native resolution is being shown natively on a lower-resolution panel is mistaken, and this guide must not reinforce that mistake. Check what is actually happening on the reader's setup: a stable native picture, a downscaled picture, or a rejection. Name it, rather than assuming the best case.

Lowering Is a Legitimate Fix

If a mode fails, the correct CRU response is usually a lower refresh rate at the same resolution, or a lower resolution at the same refresh rate, or reduced blanking timing where the reader understands it. Each of those reduces pixel clock and bandwidth. Raising the refresh rate to "fix" a failing mode is backwards: it increases the demand on a chain that has just demonstrated it cannot meet the existing demand. Lowering is not defeat. It is the diagnosis working correctly.

How to Add a Custom Mode, Step by Step

With the recovery ladder prepared and the limits understood, the how-to itself is short. That brevity is intentional: most of the work in safe CRU use is preparation and testing, not editing.

Step 1: Export and Note the Starting Point

Export the original EDID. Note the display's native resolution and refresh rate, and note the mode currently in use. Write down what is about to change, in one line: the resolution, the refresh rate, and whether the change is in a detailed resolution, a standard resolution, or an extension block. That note is what makes diagnosis possible if the new mode fails.

Step 2: Select the Correct Display and Configuration

CRU lists displays per configuration: the same physical monitor can appear under several entries when monitor combinations change. A reader who edits only one entry may find the mode missing when a second monitor is enabled or disabled. Check each listed configuration the reader actually uses, or at least be aware that the mode may need to be applied per configuration. Editing the wrong configuration entry is a common cause of "I added the mode but it is not there".

In CRU, a modified display is marked with an asterisk, and "(active)" means the display is connected and recognised by the driver. Confirm the asterisk appears on the intended display after editing, and confirm the entry is active, before proceeding. Copy and Paste in CRU copy resolutions, extension blocks, and range limits, not the display name or serial number; do not assume a pasted entry carries the identity of the display it came from.

Step 3: Add the Mode in the Right Place

For the common case, a custom refresh rate at the native resolution, add or edit the detailed resolution at the native resolution. For a different resolution, add a detailed resolution with a timing preset: the Automatic PC, HDTV, or CRT presets help fill timing values. Use Manual timing only if the reader understands timing parameters. Do not copy timing values, such as porch or sync width figures, from a forum post about a different monitor and treat them as a recipe. Timing values in forums are per-monitor examples, and publishing or copying them as a recipe invites an "out of range" result on other units. Use CRU's Automatic timing presets and the monitor's own specification.

For several ordinary modes, use standard resolutions, within the base-list limit described earlier. For modes beyond the base EDID capacity, or for range-limit or variable refresh rate edits, use an extension block, changing one block and testing before continuing.

If any value turns red, stop. Red means invalid or out of EDID limits. Lower the mode or use a DisplayID block for genuinely larger modes. Do not submit a red value.

Step 4: Save, Restart the Driver, and Watch the Clock

Click OK in CRU to save, then run restart64.exe, or restart.exe on a 32-bit system, to restart the graphics driver so the new modes appear without restarting Windows. Watch the display. If it does not return within about 15 seconds, press F8 for recovery mode, as described in the recovery ladder, and correct the mode from a visible screen. If the driver crashes during restart and is disabled after reboot, run restart.exe again to re-enable it, rather than reinstalling the driver as a first step.

A driver update can change this behaviour. A CRU override that worked on one driver version may behave differently after a driver or Windows update, because driver mode handling changes. If a mode stops working immediately after an update, remove the override first and re-test before blaming the panel or the cable. That isolation step, removing the override, is also the correct first response when a CRU override stops working after a driver update in general: the driver change is a suspect, and the override is the variable to remove first.

Step 5: Select the Mode in Windows, Then Test It

Adding a mode in CRU only makes Windows offer it. The reader then selects it in Windows display settings, and selects the refresh rate in Advanced display settings, then Display adapter properties, then the Monitor tab, per CRU's documentation. A mode that appears in the list has not yet been proven. Set it, and test it as a separate step.

Look for a stable picture. Check for flicker, tearing-like artefacts, an "out of range" message, or a picture that is scaled or letterboxed rather than native. Keep the previous working mode in mind. Windows' own "keep changes" revert timer is a safety net for a mode change made in Windows, but it does not remove a bad CRU override. A mode that black-screens on every login still needs Delete or reset-all removal, or safe-mode removal, as the recovery ladder describes. Do not confuse the Windows revert timer with override removal; they remove different things.

If any artefact or instability appears, revert immediately to the previous working mode, then remove or lower the CRU mode. A mode that mostly works, with occasional flicker or occasional dropouts, is not a successful mode. It is a failing mode that has not yet failed at a moment that mattered.

Step 6: Remove What Does Not Work, and Keep What Does

If a mode causes trouble, delete that detailed or standard entry, click OK, and restart the driver. If the trouble is the whole override, use Delete for the display and reboot, or reset-all.exe and reboot. Keep the exported original EDID and the note from Step 1, so the working configuration can be reconstructed if a later driver update or a second display change disturbs it.

Edge Cases That Change the Answer

Laptop Internal Panels

Laptop displays usually do not have scalers and cannot display non-native resolutions without GPU scaling, per CRU's documentation. To add other refresh rates on a laptop, add the refresh rate at the native resolution; the driver automatically adds it to lower scaled resolutions. Laptop panels and their drivers also vary in whether they honour EDID overrides at all. A CRU change that works on an external monitor may do nothing on the internal panel, or may black-screen it. Test on the internal panel itself, keep safe-mode recovery ready, and do not promise a laptop result from a desktop-monitor result. The two are different display paths, and success on one says nothing reliable about the other.

Some TVs Ignore Overrides

Some TVs ignore or partly ignore EDID overrides. Television firmware and HDMI handling may re-assert the television's own mode list, so a CRU mode that works on a PC monitor may not appear on a TV, may not hold after input switching, or may be replaced by the television's own mode. This is stated as "may ignore" because television behaviour varies by model and firmware, and no verified model list supports a stronger claim. Test on the actual television, and do not promise a television result from a monitor result. Television HDMI behaviour in general, including HDMI 2.1 modes, game-mode settings, and firmware quirks, belongs to the companion discussion of TV-as-monitor behaviour, and this article does not re-teach it.

G-SYNC and Variable Refresh Rate Monitors

Monitors with NVIDIA's G-SYNC processor only support a limited set of resolutions with display scaling, per CRU's documentation. To add non-native resolutions on such monitors, enable GPU scaling in the NVIDIA control panel, or use the Scaled Resolution Editor. Do not promise arbitrary CRU modes on G-SYNC-processor monitors without that caveat. Variable refresh rate ranges in extension blocks deserve the same caution as other extension-block edits: a wrong range can make a mode appear that the panel cannot hold, or hide a mode that should work. Change one thing, test it, then continue.

Multi-Monitor Configurations

As noted in the how-to, CRU lists displays per configuration, and the same physical monitor can appear under several entries when monitor combinations change. A mode applied to one configuration may be missing under another. Check each configuration the reader actually uses. This is not a fault in CRU; it is how per-configuration EDID overrides work, and the fix is to apply the mode where it is actually needed.

Driver Updates

A CRU override that worked on one driver version may behave differently after a driver or Windows update. If a mode stops working immediately after an update, remove the override first and re-test before blaming the panel or cable. This isolation step saves readers from replacing hardware for a software change, and it is the correct first response whenever a driver change and a mode failure coincide.

CRU Is Windows-Only in This Article's Scope

CRU.exe, restart64.exe, and reset-all.exe are Windows utilities. This article does not imply a macOS or Linux equivalent with the same steps. Other platforms need their own tools, which are outside this article's scope. A reader on another platform who follows Windows CRU steps will not reach a working result, and this guide does not pretend otherwise.

"Out of Range" Versus a Black Screen

An "out of range" message from the monitor itself means the monitor received a mode it cannot display. That is a timing or bandwidth fault, and the response is to lower the mode or remove the override. A black screen with no monitor message can also be a driver-restart state, as the recovery ladder's step about a disabled driver describes. Help the reader distinguish the two by the monitor's own on-screen message, rather than treating every black screen as the same fault. The message, or its absence, is diagnostic information, not decoration.

Common Misconceptions, Corrected

"CRU overclocks my monitor and makes it faster than its specification." Correction: CRU reveals or adds modes within what the panel, port, cable, and GPU can deliver. It does not raise the panel's physical capability. A mode the panel cannot hold is a failure, not an overclock success. No specific "safe overclock" refresh rate for any named monitor is published in this guide, because panel headroom is per-unit, per-firmware, and per-chain, and a forum success report for one unit does not transfer to another.

"If the mode appears in Windows, it must be working." Correction: appearing in the list only means the override was accepted. Stability, native scaling, and absence of artefacts are the test. A listed mode that flickers, drops, or scales incorrectly has not passed.

"CRU changes my monitor's firmware, so I can't undo it." Correction: CRU writes a Windows registry override. The monitor itself is unchanged. Delete, reset-all.exe, or safe-mode reset-all removes the override. The documented position is exactly that: CRU changes Windows configuration data, not monitor hardware, and a bad mode can leave a black screen until removed. This guide makes no hardware-damage promise in either direction, because neither absolute is documented.

"A higher refresh rate number is always smoother." Correction: only if the panel, chain, and GPU can hold it stably at that resolution. An unstable high rate with dropped frames or flicker is worse than a stable lower rate. Smoothness is a property of a held mode, not of a number in a list.

"If the cable connects, it can carry any CRU mode." Correction: connection proves nothing about bandwidth. A mode needs bandwidth the whole chain provides. Cable certification detail belongs to the companion cable discussion; the principle here is sufficient to prevent the error.

"Deleting the mode in Windows display settings removes the CRU override." Correction: Windows settings select a mode. CRU's Delete button or reset-all.exe removes the override. A bad mode that returns on every login needs the CRU removal, not another Windows settings change. Confusing these two actions is why some readers report that a bad mode "keeps coming back".

"CRU works the same on laptops, TVs, and monitors." Correction: laptop scalers, television firmware, and G-SYNC processors each limit or ignore overrides differently. Test on the actual display, and do not transfer a result from one display type to another.

"Red values in CRU are warnings I can ignore." Correction: red means invalid or out of EDID limits, 4095 by 4095 pixels and a 655.35 MHz pixel clock for detailed resolutions. Do not submit a red value. Use a DisplayID block for genuinely larger modes, or lower the mode.

A Safe First Test, Worked Through

A reader with a monitor whose native resolution is already correct, but whose preferred refresh rate does not appear in Windows, has the safest possible first CRU test. Export the original EDID. Note the native resolution and the current refresh rate. Add the desired refresh rate as a detailed resolution at the native resolution, using an Automatic timing preset. Do not touch extension blocks. Do not touch standard resolutions. Save, run restart64.exe, and watch the 15-second window. If the display returns, select the new refresh rate in Windows Advanced display settings, and test for a stable picture, without flicker, artefacts, or scaling oddities. If the display does not return, press F8 for recovery mode, correct or delete the mode from a visible screen, and restart the driver again. If the mode appears but is unstable, revert to the previous refresh rate, then delete or lower the CRU entry.

That single test teaches the whole method: one change, one test, a known escape route, and a willingness to lower the mode. A reader who can do that test safely can approach more ambitious modes with the same discipline. A reader who skips the export, edits several blocks at once, and submits a red value has not done a bolder version of the same test. They have done a different, unsafe test, and the recovery ladder exists for them.

Before You Start: The Checklist

• Export the original EDID, and keep it somewhere it can be found again.
• Know the CRU folder path, so restart64.exe and reset-all.exe can be found without seeing the screen.
• Keep a second display or a known-good connection available for recovery, where possible.
• Note the native resolution, the current refresh rate, and the exact change about to be made.
• Edit one thing, in the right place: detailed resolution for a custom refresh rate at native resolution, standard resolutions for ordinary modes, extension blocks only with an export and a test after each change.
• Never submit a red value. Red means invalid or out of EDID limits.
• After saving, restart the driver with restart64.exe, and watch for the 15-second return. If the screen stays black, press F8 for recovery mode.
• Test a new mode as a separate step from adding it. A listed mode is not a proven mode.
• If a mode fails, lower it: a lower refresh rate at the same resolution, or a lower resolution at the same refresh rate. Do not raise the refresh rate to fix a failing mode.
• If a mode fails after a driver update, remove the override first and re-test before blaming the panel or cable.
• Remember the central limit: CRU cannot create bandwidth, a port, or a panel. If the chain cannot deliver the mode, no EDID edit supplies it.

FAQ

Does CRU change my monitor's firmware or damage my monitor?

No, CRU does not flash the monitor. It writes an EDID override in the Windows registry, and the monitor itself is unchanged. Deleting the override in CRU and rebooting, or running reset-all.exe and rebooting, returns Windows to the display's original EDID. A bad mode can leave the screen black until the override is removed, which is why this guide puts the recovery ladder first, but the change is Windows configuration data, not monitor hardware.

I applied a CRU mode and the screen went black. What do I do first?

Wait briefly, and if the display does not return within about 15 seconds after the driver restart, press F8 for CRU recovery mode, which temporarily unloads all EDID overrides without deleting them. Once the screen is visible, correct or delete the faulty mode in CRU and restart the driver again. If recovery mode is not enough, delete the override for that display in CRU and reboot, then run reset-all.exe and reboot, then boot to safe mode and run reset-all.exe there. Work the ladder in order, and do not start by editing the registry by hand.

Why does a mode I added in CRU appear in Windows but look wrong or flicker?

Appearing in the Windows list only means the override was accepted. It does not prove the mode is stable, native, or within the chain's capability. Flicker, tearing-like artefacts, an "out of range" message, or a scaled or letterboxed picture all mean the mode has failed its test, even though it is listed. Revert to the previous working mode, then delete or lower the CRU entry. A mode that mostly works, with occasional instability, is a failing mode.

Can CRU make my monitor run at a higher resolution or refresh rate than its specification?

No. CRU cannot create capability the panel, cable, port, or GPU output lacks. It can reveal a mode the panel supports but the EDID omitted, and it can add a mode within what the chain can deliver. A mode above the panel's native resolution or above its supported refresh rate at that resolution will fail, fall back, or display incorrectly. If a mode needs more bandwidth than the chain provides, the fix is a lower resolution, refresh rate, or colour setting, not a bolder override.

Should I add a custom refresh rate as a detailed resolution or a standard resolution?

Use a detailed resolution at the native resolution for a custom refresh rate. Detailed resolutions carry a full timing definition and are the preferred method per CRU's documentation. Standard resolutions are a coarse list for ordinary modes, and NVIDIA does not support more than 8 standard resolutions in the base list. For modes beyond the base EDID capacity, or for range-limit and variable refresh rate edits, use an extension block, changing one block and testing before continuing.

What do red values in CRU mean?

Red means the value is invalid or out of EDID limits. For detailed resolutions, those limits are 4095 by 4095 pixels and a 655.35 MHz pixel clock. Do not submit a red value. Use a DisplayID extension block for genuinely larger modes, or lower the mode. A red value is not a warning to ignore; it is the first signal that the mode will fail, before a driver rejection or a black screen provides the second and third signals.

Does CRU work on laptops and TVs the same way as on PC monitors?

No. Laptop displays usually lack scalers and cannot show non-native resolutions without GPU scaling, so refresh rates should be added at the native resolution, with the driver adding them to lower scaled resolutions. Some TVs ignore or partly ignore EDID overrides, so a mode that works on a PC monitor may not appear or may not hold on a TV. Test on the actual display in each case, and do not transfer a result from one display type to another.

My CRU mode stopped working after a driver update. Is my monitor faulty?

Not necessarily, and do not assume so. A CRU override that worked on one driver version may behave differently after a driver or Windows update, because driver mode handling changes. Remove the override first and re-test before blaming the panel or the cable. If the display works normally without the override, the update changed how the override is handled, and the mode needs to be re-added and re-tested under the new driver, not the monitor replaced.

Can I use CRU on macOS or Linux?

This guide covers CRU as a Windows utility: CRU.exe, restart64.exe, and reset-all.exe are Windows tools. Other platforms need their own tools, which are outside this article's scope. Do not follow the Windows CRU steps on another platform and expect the same result.

When to Seek Help

If the overrides have been removed, through Delete, reset-all, or safe-mode reset-all, and the display still does not behave normally, the fault is no longer a CRU override, and further CRU editing will not fix it. At that point the diagnosis broadens to the cable, the port, the GPU output, and the display itself, in that order, with a known-good cable on the shortest direct path as the first test.

For readers in Hong Kong who would rather have a display problem assessed in person, HK GPU Fix is located at Dali Plaza Room 1209, Shek Mun, Shatin, phone 2186 8010, WhatsApp 6558 6806. Bring the monitor details, the cable in use, and a note of the exact CRU change that was made, including whether the original EDID was exported, and the assessment can start from the actual chain rather than from a mode list.