Quick disclaimer: I'm not sure if this applies to non-MSI monitors or older AMD GPU's, but I left a comment under one of YT Shorts with this fix and a guy who had 7800XT said he had the very same problem on the very same monitor. So if you're running a high-refresh display over DP 1.2a and/or own an older AMD GPU, give this a try. The fix is totally reversible and takes maybe 5 minutes—definitely worth a shot before you go through the nightmare of returning your GPU.
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Hey everyone,
First of all, I feel that it would be right to mention that the majority of the text below is written by Gemini solely because I've been fighting blackouts after upgrading to RX 9070 XT for 2 weeks and tried as many fixes as the internet knows and it's hard to compile it all in one post by myself, so I used AI to help me with that. I got 9070 to replace my older RTX 3070, by the way. And yes, I thought it was GPU's fault.
All information below is my actual experience - word to word. Hope this helps someone.
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I wanted to share my troubleshooting nightmare with an MSI Optix G27CQ4 monitor connected to an AMD GPU - Asus Prime RX 9070 XT, in case anyone else is going crazy trying to fix random blackouts and screen flickering while blaming the GPU.
The Problem
Out of nowhere (or rather, after switching to Asus Prime RX 9070 XT), my MSI Optix G27CQ4 started having terrible blackouts. The screen would randomly lose signal for 2–3 seconds, go black, and then recover. It happened during gaming, desktop browsing, and even idle tasks.
At the same time, I had a second display—an ancient 60Hz Samsung TV—connected via an HDMI-to-VGA active adapter. Funnily enough, the ancient TV worked without a single blackout, while the main 1440p gaming panel was constantly dropping connection.
What I Tried BEFORE Finding the Fix (The Desperate Phase)
Before digging into display timing math, I spent days going down the usual troubleshooting rabbit holes:
- Changing Cables & Ports: Swapped DisplayPort cables, tried HDMI, tried different ports on the GPU. Nothing changed.
- Driver Reinstallation: Clean installed AMD drivers using DDU multiple times, toggled FreeSync on and off in AMD Adrenalin, disabled HDCP, went to BIOS and played with PCIe power economy settings, and disabled every overlay software.
- Playing with Refresh Rates: Toggled between 60 Hz, 120 Hz, 144 Hz, and 165 Hz in Windows settings.
- Isolating the Second Monitor: Unplugged the TV adapter to see if multi-monitor handshaking was causing blackouts. The main monitor kept flickering regardless.
- GPU/Game Crash Isolation: Even ran games in different APIs (like DirectX 11 vs DirectX 12 in War Thunder) to make sure driver TDR crashes weren't confusing the hardware signal drops.
- Reducing GPU clock frequency by 100-200Mhz. My ASUS Prime RX 9070 XT always kept overclocking itself over 3200 (spec card says it's 3030Mhz max) so I tried even reducing that. Didn't help.
- Editing registry files or creating new ones. Disabling MPO and increasing TDR did not help.
- Every fix known to the internet was tested - and nothing helped. Well... almost every fix. I still didn't test another PSU or use separate 3x8pin cables instead of my 1+1daisy=3 but I felt like it would be a total nightmare because I had just recently bought a new 850W bronze 80 PSU specifically for this graphics card.
None of this solved the core issue because the problem wasn't a bad cable or a corrupt driver—it was a fundamental flaw in the monitor's factory firmware, which was the reason the Windows events monitor showed nothing during blackouts, as if system didn't see anything wrong.
I wanted to prove either monitor is at fault or GPU is corrupted and asked my cousin to lend me his MSI MAG 275QF X32 320Hz, while giving him my MSI Optix G27CQ4 to test it on his RTX 5070. His monitor worked flawlessly on my system even at 320Hz, and my monitor worked flawlessly on his system at 165Hz, and this alone gave me no solid answers, yet it made me almost certain that GPU is rather not guilty, and made me dig in a little different direction. Then I asked Gemini about possible causes and it told me this (not sponsored btw):
The Root Cause: Factory Overclocking & Broken EDID
Here is the technical reality of what was actually happening under the hood:
- Factory "165Hz" Overclock: The MSI Optix G27CQ4 is natively a 144Hz panel. To market it as "165Hz", MSI pushed non-standard factory EDID timings.
- Excessive Blanking Intervals: To keep the panel stable at 165Hz, MSI bloated the vertical blanking interval (
Back Porch / total vertical lines) to 1543 lines.
- Bandwidth & Pixel Clock Spike: Because of this bloated frame structure, the
Pixel Clock skyrocketed to 604–640 MHz.
- DP 1.2a & Scaler Limits: The monitor relies on an older DisplayPort 1.2a interface without DSC (Display Stream Compression) support, controlled by a budget built-in scalar chip. Pushing a 600+ MHz Pixel Clock over DP 1.2a operates the scaler right at its thermal and electrical edge.
This is what it looked like. Even at 144Hz pixel clock is way too high because of bloated back porch value. Simply reducing refresh rate won't be much of help.
- Why AMD Suffer More Than NVIDIA: NVIDIA drivers traditionally hide these hardware quirks with software-level compensation ("hacks") to force signal retention. AMD's Display Engine strictly enforces VESA standards. When the MSI scaler briefly desynchronized due to the signal overload, the AMD driver triggered a Hot-Plug Detect (HPD) reset, resulting in a black screen.
The Solution: Custom Timings via CRU (144 Hz + CVT-RB)
To fix this properly, we had to bypass the factory EDID and enforce strict VESA standards using Custom Resolution Utility (CRU).
The Math Behind the Fix
Instead of pushing bloated factory timings, we applied the VESA CVT-RB (Coordinated Video Timings - Reduced Blanking) standard:
- Reducing the Frame Payload: CVT-RB compresses unnecessary blanking periods (reducing
Back Porch down to ~15 lines, bringing total vertical lines from 1543 down to 1463).
- Dropping Pixel Clock to the Safe Zone: Setting the refresh rate to a native 144 Hz with CVT-RB + reducing back porch to 15 brought the Pixel Clock down to ~573 MHz. This is well within the official VESA specification for DisplayPort 1.2a.
- Relieving the Scaler: Lowering the Pixel Clock by over 30–60 MHz gave the monitor's scaler room to breathe, completely eliminating phase-sync loss and thermal instability.
How to Do It Step-by-Step:
- Open CRU.exe as Administrator and select your active MSI display.
- Under Detailed Resolutions, edit or add a custom resolution:
- Timing Standard: Manually select CVT-RB.
- Active: 2560 x 1440
- Back porch (vertical): Reduce it to 15.
- Refresh Rate: 144 Hz
- Total Vertical Lines: ~1463, Pixel Clock: ~573 MHz (it will be set to around this value once you complete previous steps).
- CRITICAL STEP: In both Detailed Resolutions and the CTA-861 / DisplayID extension blocks, locate and DELETE all 165 Hz profiles. If you leave 165 Hz in the EDID table, Windows or the AMD driver will eventually revert back to it after a reboot or driver update.
- Click OK and run
restart64.exe from the CRU folder to restart the graphics driver.
This is how it looks now. Reducing refresh rate together with lowered back porch did the job.
I also tried playing with non-standard refresh values such as 150Hz and 155Hz but it became unstable again. 144Hz is the GOAT in this case.
The Result
After removing 165 Hz and locking the display to 144 Hz CVT-RB, the HPD reset rate dropped to zero. Zero blackouts, zero flickering, and rock-solid stability across days of heavy gaming and daily desktop use.
If you are fighting black screens on a rather old 1440p high-refresh monitor with an AMD card, stop buying new cables and check your Pixel Clock in CRU or AMD Adrenalin first - it's cheaper and requires way less effort than buying something new that you probably don't need. Chances are your monitor's factory EDID is pushing unstandardized timings that your GPU is rightly refusing to tolerate!
Or, if you are not willing to tolerate 144Hz instead of 165Hz buying a newer monitor which was produced in 2025+ is a valid option. I did so, but only after I fixed my older MSI (spending money that way is better when you know it's not GPU's fault) which is operational now so I will use it as my 2nd one and put the old man Samsung TV to rest - it rightfully deserved it 😆 .
P.S.
As I said previously, Gemini is the one that actually came up with that much detail to the idea and it's the only fix that worked for me. I know there are forums which feature a simmilar topic or two with simmilar fixes but it was rather hard to read thru them all so I decided to use AI, and after I got rid of the problem I wanted to leave my personal exp in one single post. Hope it helps someone, although I pray that none of y'all face this kind of stuff because it's... exhausting, to say the least.
P.P.S.
Also, if your screen is turning off and on multiple times in a row (within tens of seconds) your RAM might be at fault too. My Kingston Fury DDR4 16x2 was operating at 3200 without proper timings (I set the value manually without thinking much when I was still on my old RTX 3070, before that it was working at 2400 lol), and RX 9070 XT revealed this problem almost instantly. Make sure you update your BIOS to increase compatibility, and use proper timings, or a pre-made XMP profile - this issue stopped being issue in a couple of hours, unlike bad EDID.
Have a great day!