HDMI / Display Port Cables Can Cause Your GPU To Appear Dead / Bricked

1 : Anonymous2021/07/04 08:14 ID: odg3ee

Hey, felt the need to offer a small PSA.

I have just had a hell of a time dealing with an incredibly stupid and specific issue. A perfectly normal-looking HDMI cable was causing my 6800 XT to produce black screens after bios, but would function in Safe mode and Bios correctly.

This normally points to a dead video card, however, through hours of testing everything from a riser to pcie slots to OCs, vbios flashes, More Power Tool, Soft Power Play Tables, power connectors, PSU, motherboard bios configuration, and completely disassembling and reassembling my entire PC.. that a f***ing HDMI cable short, on an undamaged perfectly normal looking HDMI, was causing my GPU to bootloop once I logged into Windows. So, PC is stable, GPU bootloops, evidenced through fan RPM responses and the RGB led radeon logo turning off then back on again.


This is probably obvious to most people, *but it can be extremely confusing if it only fails some of the time.*

In my instance, both the Bios and Windows safe mode were working, which meant that the cables were functioning, or at least, not f***ing up other components, at least some of the time, hence why it was such a late thing that I tried.

Anyway. Hope this helps someone else, Thought I bricked my midnight edition and had a slightly emotional few hours resetting and reassembling a PC.

Cheers, hope I help save some people's time. <3

2 : Anonymous2021/07/04 09:46 ID: h40bgu1

I've had a cheap DP cable cause my CPU fan to stop spinning. System booted fine, but the room felt noticeably warmer, and my games kept crashing. Learned about the "pin 20" issue. That was fun.

3 : Anonymous2021/07/04 11:57 ID: h40jx0r

Some display port cables will cause blinking blank screens even when not gaming. Bought one from Amazon for $4 should have read reviews first lol.

ID: h40poxb

There's so many cables on amazon that don't meet specifications and shouldn't legally be sold, it's crazy.

ID: h417pin

At this point, I'd rather get ripped off at Currys/Argos then buy Chinese no brand junk from Amazon.

ID: h40pyo9

Yes had to go to Microcenter and grab last Belkin cable from like 2012 since my monitor is only 1.2 spec but it was only $5 on clearance. Bulky but works, will be upgrading to newer monitor soon and will make sure I pick right hdmi / dp port cable this time around even if it’s not a budget one.

ID: h42bmbt

Cable specifications are not law...

4 : Anonymous2021/07/04 11:07 ID: h40gjbk

Crap DP cables (with the DP power connected) can bring down while PCs with ease. Always check your cables.

ID: h40h5ga

It was just shocking that instead of a NO DISPLAY signal from my monitor, it caused the GPU to bootloop. Crazy.

ID: h40ngkr

Had a brand new PC not even power on because of a DP cable....

5 : Anonymous2021/07/04 09:15 ID: h409lau

Had a smiliar problem with flicker, tearing and screen blinking on my 1080 Gtx with an Asus PG279Q G-Sync. Somehow my AMD Chipset was running an older version. All my problems went away after installing latest Chipset drivers. Using Fiber DisplayPort 32.4 Gbps cable.

6 : Anonymous2021/07/04 13:12 ID: h40q2gs

Good display cables are EXPENSIVE. Think at least 20usd. You can check if the cable is VESA certified which is a 100% guarantee it will work for that standard. Don't buy cheap shit, it will bite you in the bottom.

7 : Anonymous2021/07/04 16:45 ID: h41env7

My defectively wired DP 1.4 cable was causing my x570 Aorus Master to "play dead" on 2-3 occasions well over a year ago. Then I discovered that reseating the CMOS battery after removing it and letting it discharge for a short while brought it back to life after each occurrence. Apparently, the defective cable was allowing a trickle charge to build up on the motherboard so that when critical mass was reached, the board's built-in UL protection circuitry shut down the motherboard before permanent electrical damage could result. Replacing the DP 1.4 cable with (link below) a VESA-certified DP 1.4 cable resolved the problem, and I've never had another incident! This was a real head-scratcher in the beginning...whew...

The interesting thing here was that the old cable was booting into Windows fine and running my software, so that made it even less obvious that it might be a defective DP cable. Live and learn...!

8 : Anonymous2021/07/04 16:13 ID: h41aqyx

You're right, and when it's a cable that's been working fine for a while it can be extra confounding. Had a similar experience with a VGA cable on an office PC, back when I worked at a place where they had no real IT person, so as the guy who "knows computers" they'd drag me over for every little issue like this.

Thankfully, I was able to realize that everything was working (fans were spinning, audio was playing, etc.) but there was just no display output, so I started by checking the cables (because dragging an entire new monitor over would've been a pain and I wanted to eliminate the simple issues first) and luckily for me, that was the issue.

Put in a new cable, and thankfully, that's all that was needed. Didn't have to drag a new monitor or desktop tower out of storage.

9 : Anonymous2021/07/04 22:43 ID: h42kzuu

A friend of mine had to spend weeks troubleshooting why his brand new 3950x/x570 rig had trouble POSTing, had trouble waking up from sleep and why it had issues even accepting keyboard inputs in BIOS.

Turned out it was a cheap ass DP cable causing the trouble. Lesson learned: don't buy shitty cables off of Aliexpress

10 : Anonymous2021/07/04 22:35 ID: h42k6m9


All caps? I'm confused by how important you seem to be wanting to make this point since it really isn't true, and was actually your experience.

11 : Anonymous2021/07/04 21:09 ID: h42ais5

I love HDMI. It's simple, it's digital and it's dirt cheap. Back in the day I paid over 30 bucks for a "premium" DVI cable, gold coated and all the fixings. It had an annoying issue with solid red bars across the screen randomly when playing games. Also the annoying screws would always unscrew the screws in the graphics card. I then purchased a 2 meter HDMI cable for 8 bucks (which is also gold coated) and I'm still using it 7 years later. Not a single issue.

12 : Anonymous2021/07/04 20:13 ID: h423t98

Dirty power can cause instability too. I'm not talking about PSUs here. If you have a lot of devices drawing power on one line (one line - not just one wall socket) that can lead to instability.

This is one reason many people use a UPS for their PCs, or in the case of audiophiles run a dedicated line to their setups.

13 : Anonymous2021/07/04 19:43 ID: h420c0u

produce black screens after bios, but would function in Safe mode and Bios correctly.

This normally points to a dead video card,

I've never seen that be an indication of a dead video card.

ID: h426ozv

wouldnt a dead video card simply not output anything, hence the adjective "dead"????

14 : Anonymous2021/07/04 15:42 ID: h416xcc

I had problems for a long time with pc not being able to post after reboot, cpu temp showing -57c and some other weird stuff. Turns out it was my DisplayPort cable that wasn't up to VESA specs and was transmitting power on pin 20, which messed my whole system up.

Be absolutely sure your DP cable does not transmit power on pin 20 unless you for some reason have a device that actually requires it.

ID: h416zcp


DisplayPort (DP) is a digital display interface developed by a consortium of PC and chip manufacturers and standardized by the Video Electronics Standards Association (VESA). The interface is primarily used to connect a video source to a display device such as a computer monitor, and it can also carry audio, USB, and other forms of data. DisplayPort was designed to replace VGA, FPD-Link, and Digital Visual Interface (DVI). The interface is backward compatible with other interfaces, such as HDMI and DVI, through the use of either active or passive adapters.

[ F.A.Q | Opt Out | Opt Out Of Subreddit | GitHub ] Downvote to remove | v1.5

15 : Anonymous2021/07/04 15:29 ID: h415ff3

If bsod continues get new cable, perhaps a new HiSpeed 2.0 version on up,or try another same HDMI. It really is ok.

Actually they somehow shake a bit free from time to time, and wiggling it may cure it.

16 : Anonymous2021/07/04 10:28 ID: h40e2io

OK. I was advised once to do it like that . And it worked for me .

17 : Anonymous2021/07/04 08:46 ID: h407uzs

thank you for the info! my mate got a similar issue with his aoc monitor and a rx5700xt nitro which sometimes doesnt get a signal from the monitor ...he fixed it by re attaching his displayport cable which is from club3d he told me.

18 : Anonymous2021/07/04 12:49 ID: h40nyzb

One of the things I learned from Jerry Pournelle's columns in Byte magazine back in the dawn of the PC age was that whenever there's a problem, it's _always_ the cable.

19 : Anonymous2021/07/04 10:09 ID: h40cx3b

This might help. Tune your devices off that the hdmi cable us connect to and pull the plugs out and or pull the power cables out Unplug both ends of the Hdmi cord for 20 minutes . Then put the hdmi cord back in the reverse way and turn everything back on. This might help you. It work for me when similar thing happened

ID: h40dqbx

20 minutes? Why 20 minutes? All electric charge should be dropped in <60 seconds

ID: h41wkar

It give time for your devices to cool down as well.

20 : Anonymous2021/07/04 08:48 ID: h407xdt

Thanks for posting your experience. It's useful to know that an HDMI cable can cause such problems.

It still seems to me like it's a driver bug and should be reported. I seem to remember that AMD prided itself once on a new ability to detect a bad HDMI cable. Can't find the reference now, but I think it was a new feature at one point in recent years. It may be that this functionality is causing an issue. In any case, I don't think that a bad cable by itself should be causing a boot loop unless there's a software component failing as a result.

ID: h40gaak

This is not a driver bug. Tested with drivers going as far back as a year

ID: h40htk8

That doesn't mean much. There are driver bugs going back more than a year. It's possible that it's even a day 0 bug. If the OS reboots, there's a good chance it's a matter of software, or at the very least can be solved in software. It's possible that it's not a bug in the drivers but in the OS, but I think it's less likely.

I think it will be good to report this to AMD. They might pick it up from this sub, but it's better to be proactive about it.


Notify of
Inline Feedbacks
View all comments
Would love your thoughts, please comment.x