Question Old GPU: artifacting (even before Windows boots) and no image; suspect that the PSU is the actual culprit - second opinions please?

Dec 14, 2019

I have an old (12 years old) desktop running Windows XP. Yes, I know, this sounds bad. After this PC became obsolete for all intents and purposes, it just sits in the corner and I use it sometimes for storing / backing up stuff on its hard drives (which are still in good shape) and sometimes playing an old game or two. That kind of stuff. If it ain't broke and still does its job, don't fix it.

It has a Asus P5KR motherboard with a Sapphire Radeon HD 2600 XT - 512 MB GDDR3 - PCI-Express 1.0 x16. A medium-level GPU from 2007. Had some occasional overheating episodes in the past (long time ago), but it's still alive and kicking.

Catalyst event:

A couple days ago, in my presence, the PC experienced what I believe was a barely-recoverable GPU failure during runtime. The entire OS froze for several seconds (including the cursor, and the playing music got paused too), hardware acceleration of video got forcibly turned off in a media player software (saw it in the tray notification), the desktop background became the typical random dump from video memory, and fonts in each new text field that I opened (new menus, new tabs) became slightly mangled. Also, general performance dropped by a lot, instantly. I turned it off with a button press.

Since then, the behavior of the GPU is as follows:

  • most of the time, on boot, there is no image on the monitor at all. The monitor is connected with DVI, which is native for itself and the GPU. The monitor's default behavior here is alternating between Analog and Digital interpretation of the input, and evidently it receives nothing in either mode. This is different from "No signal - check cable" which happens if you unplug it from the GPU. Thus, the monitor "recognizes" some presence on the other end, there's presumably at least "some" signal, but there's just no image.
  • sometimes, on boot, the image appears on the monitor normally during the initial boot sequence (before WIndows boots). However, in the first few seconds, it's highly likely to become corrupted with artifacts in the form of thin lines or semi-transparent squares (still in 640x480 text mode). If it does become corrupted like that, then during the next few seconds, the image disappears altogether.
These states seem to be "not recoverable", the image doesn't reappear even if I wait. However, the actual boot procedure happens as usual, just without any image. I'm sure of it from LED blink sequences, sounds from peripheral devices, etc. It reacts to the keyboard the way it should react if I press it at a certain stage. The initial beep reports no problems, too, even if there's no image since the 1st second. (for the record, if I remove the GPU completely, it does signal about that).

* but rarely, the boot sequence goes through without any artifacts, Windows successfully boots, and from then on, everything is very stable. The system then works for hours without fail, 3D games work without artifacts. It really seems like it's hard for the GPU to "survive" through the initial boot sequence, but after that it's smooth sailing. Something I know about the boot sequence is that, normally, the image cuts out for a split second and reappears again between "stages" of booting. I know this from the way the monitor subtly reacts to a re-appeared signal. So my best guess is that the GPU can't handle all this switching.

It gets weirder

I shopped locally for a replacement GPU (second-hand for cards from 2007, of course). At first I wanted the exact same model to save me some headache with drivers, but it wasn't available. However, one seller had a HD 2600 XT Ultimate, which has 256 MB of GDDR3 (as opposed to 512 on mine) and passive cooling without an active spinning cooler. Before buying the XT Ultimate from him, I personally saw him plug the Ultimate into his test rig and it worked without fail. GPU-Z also showed that it's legit. Out of curiosity, we plugged my old one too (I had it on me), and it showed artifacting on his rig too (although a bit less severe). Evidently, my old card was dying, and this new one would replace it well.

However, after plugging the new one into my own PC, I get no image, full stop. Not in a single boot attempt, as opposed to my old faulty card. More curiously, the "pre-boot" time is much longer with this one. When I press the Power button, fans spin for some 10 seconds or so before any other activity picks up. Once, I actually had an endless reboot loop stuck in this state (only once though). I can't get it to show any image, even artifacted one. I'm positive that I installed it properly, just the way I did the old card (which I then re-installed again - and it does try to work). The new card doesn't require its own power lines, and actually it consumes a bit less power. It should be working, at least it should be showing the POST message etc - I tested it just 2 hrs prior on another person's rig - but it shows no image, at all.

Meanwhile, my old faling card still does show image occasionally, and even manages to "survive" until Windows boot sometimes. If it does, it works flawlessly in Windows, even under load.

Other observations and thoughts - am I wrong here?

I think - but I'm not sure - that if I keep the monitor physically unplugged from the electric socket in the wall (but not from the GPU) during the initial stages of the boot sequence, when there are several designated events of re-initiating the video feed - then the GPU has a good chance of successfully surviving the boot.

The perfectly normal (as far as I'm aware) new GPU (XT Ultimate) doesn't show anything at all. It does get warm though, so I assume that it is powered. I don't know how else to check it.

I think - but it can be my imagination - that when I was flicking the physical on/off lever on the back of the PSU between re-assemblies, once the lights in the room dimmed for just a tiny fraction of a second. Not really sure about this. It was during "turning on" the PSU (not the power button for the motherboard).

Lastly, the GPU had been experiencing very minor visual artifacting for the past few months. A tiny bit of horizontal-looking digital static in some evenly-colored things on the screen. Occasional and almost unnoticeable. Extremely occasionally (just several times), I had moments of the screen cutting to black and then recovering in a second; when it seemed to get stuck in this loop of on-off, I would just physically turn off the monitor for a few seconds and turn it on again, and it would be gone.

At first I was thinking it's the monitor's fault. The monitor survived a death of its own external power source a few months ago, after electricity got cut off in the area briefly. That surge, or whatever it was, fried the monitor's PSU brick. It runs well on a replacement one now, but has a small line of dead pixels in a corner.

Is it the (slightly) damaged monitor dragging my GPU towards death? Can it do that, even? Or maybe is it my computer's PSU dying and possibly taking the GPU (and the monitor) with it? Is it even possible that the fact whether or not a monitor is powered up affects the load on the GPU (and/or PSU)?