Random pixels on screen with Asus 6850

[SheepBeast]

I recently bought a 3rd hand Asus Direct CU 6850 from the MM. It's been running well - no excessive noise, temps hitting max of about 70 when gaming.

However I am experiencing intermittent pixels on the screen which seem to appear at random, and exhibit a random colour. Some of the pixels flash. I can go for several hours with no problems at all, and then suddenly it'll start up again. Closing a window or opening a new one affects the dots - it either makes them go away completely, or makes them shift into a new pattern. Sometimes there are only 1 or 2 pixels, and sometimes up to maybe 20 or 30.

I've had no other problems with the card. No game crashes or freezes, high temps or low frame rates. The random pixels only appear about 10-15% of the time, and even when they are on screen they aren't numerous enough to bother me that much. If this is as bad as the problem gets, then I'd be happy enough to put up with it as I plan to get a new card in September anyway, so it's not like I'm stuck with this one forever. But I'm worried the card may be a bit duff (since it's 3rd hand), and that the problem could get worse. If the card goes, it might take out my mobo too and I can't afford a new card & mobo, therefore I'd be left without a PC. I need my PC for uni work so it's quite a big deal.

Does anyone have any idea what could be causing the problem or how I could go about fixing it? I don't know what MM policy regarding problem items is so I'm going to e-mail a mod about it, but I'd much rather fix the problem, or just put up with it (if you guys think it won't get worse) than cause a fuss trying to get my money back. Alternatively, is it possible the card still has a manufacturer warranty? I was told by the seller it's around a year old.

 

[IvanDobskey]

Sounds like you could have some dodgy VRAM unfortunately.

 

[SheepBeast]

Bump.

Really need some help with this. It seems to be getting worse (percentage of time for which pixels are on screen is now around 30-40%).

To give some extra detail, when I move the mouse across the pixels it doesn't affect them. They are still there when the cursor moves away. But when the cursor is on top of them, they are invisible, like they're hidden behind it.

I would have though that dodgy VRAM would mean that any form of refresh for the pixel, whether it be a new window or a mouse cursor moving over it, would alter it?

 

[J.D]

Can you try the card in another PC?. This could rule out the card as the culprit but it looks like it could be the card. I don't know how the MM works when it comes to faulty equipment but the Mod's will keep you right.

 

[SheepBeast]

Yeah I'll do that, haven't had the time recently but I'll do it over the next couple of days.

The random pixels only ever appear after or during the windows login screen. They are never present in the BIOS. Would this indicate it's a compatibility or driver problem rather than a hardware one?

 

[ALXAndy]

Yeah I'll do that, haven't had the time recently but I'll do it over the next couple of days.

The random pixels only ever appear after or during the windows login screen. They are never present in the BIOS. Would this indicate it's a compatibility or driver problem rather than a hardware one?

I have had cards do this when loaded with a driver.

Boot into safe mode however? they "work?" fine.

Until the driver loads (at the welcome screen) your card is not being used. Once the driver loads it then uses the card's functions, which is when (if one of them is failing) you will have issues.

Safe mode deliberately avoids loading any drivers incase they are what are preventing you from entering Windows in the first place.

Edit. So basically until you get to that Windows screen your card is not being "loaded" or used properly. No 32 bit colour, no fancy effects (Aero) and so on. It is being used in 256 colour compatibility mode which is why the problem does not show up prior to the welcome screen.

HTH

 

[SheepBeast]

snip

Yeah, but the card is being "used" to some degree to output the display to the monitor. for example each frame must be loaded into VRAM before it's displayed surely? So if faulty VRAM was the problem, then the pixels would be present in POST/BIOS too?

I've had a card before with a similar problem to that which I'm having now (but much worse in degree) and the artefacts were present both before windows started and after. But for my current card, it's only in windows.

 

[SheepBeast]

bump

 

[SheepBeast]

Ok update: I've ensured all drivers from previous cards are cleaned from my PC. Still having the dots problem intermittently. Currently thinking the "bad VRAM" is looking to be the problem. Anyone had similar issues before? Will it get worse, or break altogether? Or just remain the same? If it's the latter, I'll just put up with it