Little Green Dots

[DigiMatInc]

Not sure if you can help with this one. And apologies for the wall of text

Couple of months ago I noticed on the windows desktop a "rash" of green pixels across the middle of the screen. At the time I assumed that I was overworking the graphics card (an MSI 7300gt) - the issue seemed to be intermittant - over the following months they'd appear and disappear, only visible when certain colours were displayed.

I assumed a new graphics card would fix the job permanently. No such luck. I ordered a Sapphire 2900 512 Pro last week and a coolermaster 500w PSU. Both were a mistake – the card I wanted was out of stock and I evidently selected the wrong PSU.

Anywho notwithstanding the fact that having installed my new graphics card, my PnPSE drivers corrupted again and I ended up reinstalling windows (upon which I discovered that my windows OEM number was invalid and ended ordering a new XP activation code) the new graphics card/PSU installation went well.

Apart from the dots. They're back - and worse - now "on" all the time

> Firstly, they aren't stuck or dead pixels. If I display a fully black screen they aren't present. I also ran an "unstick your pixels". It didn't help.
> It's not the screen. The pixels don’t appear pre-driver loading in windows (so throughout the boot and windows welcome screen). I've reseated the cables.
> I don’t think it's the card. The old card had it and the new one does too. I have the latest drivers. I've reseated the card too, checked the fan runs. I can't have cooked it yet - I've not run the PC for more that a few hours since the new card went in – and I’m not a hardcore gamer anyway.
> It's not the card drivers. I've uninstalled them and on reboot of windows in standard VGA mode (before winxp sees the card) they're still there.
> It's not windows. I've done a full repair installation (not just a console repair)
> I guess it might be the mobo. I've installed the latest chipset and CPU drivers from their respective parents.
> I guess it might be power. It's a new PSU, 500w which might not be man enough? I removed my extra CD drive and HDD just in case it was to do with drawing too much power, which unsurprisingly didn’t help
> It's not malware. I rann Spybot S&D, Spyware blaster and Nod32 AV scans. I've run a registry checker too.
> It’s not my eyes. I’ve had the dots independently verified by my wife and brother. At my age, it seemed like a logical step.
> It's not me: I'm not a HC gamer, haven't overclocked anything or have any fancy software running.

I've done research on the web and come across people with the same problem although not a consistent answer. Someone said it comes from running an 8x AGP card in a 4x slot but that doesn't affect PCI-E cards? Quite a few people said it's caused by bad video ram, but then since it's present on both cards I don’t see how it can be? I haven't tried reinstalling my old card yet but might give that a shot. I've tried running ATItool to underclock my card (which might cure a bad ram problem) but it hangs, so I need to get RivaTuner and try that.

Things left for me to do:
> Try and get a screenie
> Get Riva and underclock the card
> Ask you all for some ideas

Setup
ASUS M2V Mobo, VIA chipset
AMD dual 64 4200s
Sapphire ATI 2900 PRO HD graphics card
2gb ram
500w PSU
Win XP, SP 2
Samsung 22 widescreen LCD

Thanks in advance

[peterb]

Although you have ruled out the screen, what happens if you display a fully white page? If thye red and blue pixels are not illuminating, then the result would be green dots.

Other possibility is that you are not running the screen at its native or preferred resolution, and it is some form of aliasing effect, but it seems strange that it dpoesn't appear at boot up. Does changing the resolution once windows is running make any difference?

[DigiMatInc]

Although you have ruled out the screen, what happens if you display a fully white page? If thye red and blue pixels are not illuminating, then the result would be green dots.

I displayed a fully black screen and couldn't see them. I'll try white.

Does changing the resolution once windows is running make any difference?

Just so I make sure I've understood - you mean change to, say 640x480?

[peterb]

Yes, change the display size from within windows. (try a couple) And then make sure you are running it at the 'correct' (optimum) resolution for the monitor (should be in the manual)

[Bugbait]

I displayed a fully black screen and couldn't see them. I'll try white.

Sounds like a monitor/pixel issue to me. Google "dead pixel tester" which allows you to use a full spectrum of colours and patterns. A black test isn't really sufficient to rule it out. A pixel can be always on, always off, or just partially (some primary colours aren't working) broken as perterb suggested.

[stevie lee]

have you tried a different monitor on the graphics card? this will see if its a monitor problem..

if you have no other monitor, what about the cable? check for bent pins, kinks, is it in the slots properly?

magnetic interference from speakers or other things?

[DigiMatInc]

Sounds like a monitor/pixel issue to me. Google "dead pixel tester" which allows you to use a full spectrum of colours and patterns.

I realise that I failed to mention that some of the green pixels pulse/flicker. This is particularly evident around bright screen areas - such as a sun in WoW. Apologies.

I googled "stuck pixel tester" since I imagined a dead pixel would be dead from the get-go and therefore visible in the windows splash screen. I ran "stuck pixel" for about an hour with no visible improvement.

have you tried a different monitor on the graphics card? this will see if its a monitor problem... if you have no other monitor, what about the cable? check for bent pins, kinks, is it in the slots properly ... magnetic interference from speakers or other things?

Dont have a different monitor - planned to try plugging my laptop into it tonight to see what happens. I'll have the cables out and move my speakers too. Wasn't aware that speakers interfered with LCDs like they used to CRTs - a "degause" function would be handy.

Thanks for advice so far.

[vinnyT]

Does this occur in safe-mode?

It's a good idea to try the monitor on your laptop, it will help eliminate at least one possible cause, if you're lucky the monitor will display the green dots and you'll know that the problem is the monitor.

[DigiMatInc]

Does this occur in safe-mode?

Good catch - and I don't know - will try and report back. However, when I removed the card drivers via XP and booted to standard vga mode the dots were there.

[DigiMatInc]

OK, some answers:

1. The green dots DO NOT appear when connected to my laptop.
2. The green dots DO appear if I use the SVGA/HDI adapter and connect via analogue jack on my monitor

I think that just about rules the monitor out.

3. They DO appear if I switch resolutions/refresh rate
4. They DO NOT appear on full screen white page
5. They DO NOT appear in windows safe mode. I need to figure out how to change the wallpaper to something that works in safe mode without a mouse - long story, no short version.
6. They appear in DVD playback

Assuming they do NOT appear in safe mode, WTH does that mean? I'm up to date with all my drivers and XP updates...

Screenie (I hope). Drawn around problem areas in black (in case you think they're dead pixels!)



On other odd thing. Last night I was in WoW watching the smoke drift off a fire. The edges of the smoke pixellated and turned green and went with the smoke across the screen. I know it sounds weird, but I know what I saw - I couldn't catch a screenie of it. So now I'm thinking that bad video memory might be the culpritt

[Bugbait]

Seems to be a problem when using higher bandwidth in the cable. If you're using the same cable for the GFX and laptop then I'd focus on the GFX card. Do the green dots change if you wiggle the cable while it's connected to the GFX card?

[vinnyT]

"Assuming they do NOT appear in safe mode, WTH does that mean? I'm up to date with all my drivers and XP updates..."

That would suggest that the prob is driver related (which is not loaded in 'safe-mode'), possibly the gfx driver but you've already discounted them in your first post, so try stopping all but necessary (by necessary I mean anti-virus, anti-spyware and firewall) startups in msconfig (or, better, autoruns AutoRuns for Windows) and see by trial and error if this makes any difference.

[DigiMatInc]

OK can confirm:

> Get the dots in safe mode
> Get them when connecting via VGA cable (rather than DVi)
> At reduced resolution and colour depth.
> If I adjust the contrast of the monitor right down some dots disappear, others appear elsewhere in the screen

So I'm thinking monitor? Anyone else got anything left?

[vinnyT]

Other than the screen being at fault, I have no other suggestions, sorry.

[DigiMatInc]

I'd like to take the time to thank everyone for their help. Much appreciated.

I'm going to borrow a friends screen and try that - failing that, I'll upgrade the PC