Odd 'scrambling'?

[ohtheknives]

Howdy. New user here.

I've been having this odd problem for the last few weeks and I really don't know what the cause is, so I've posted here under the general XP forum. I can't find anything at all it seems on a search for it, either.

A few weeks ago I went to open Steam, Valve software's launcher programs for games such as Half-Life 2, etc. Well, when I did, my screen decided to "scramble" and no matter what I did, it would not go away until I restarted. Well, I figured it was a minor rare occurance so I disregarded it.

It's happened a few more times when opening Steam. And also, I work with friends, some with slow connections, on a Half-Life 2 modification project, and we use Megaupload to share files (the free service option.) Well, at 10 seconds before the download a little window pops up, and over the last few weeks, 80% of the time it pops up, my screen scrambles again.

I use NOD32 Antivirus and I've scanned daily to make sure I don't have any kind of virus, and I even used Trendmicro's Housecall to see if it'd pick up anything NOD32 didn't, and it didn't. So I'm sure I don't have a virus/spyware/adware/whatever. Also, my computer had functioned perfectly for a long period of time before this started happening.

The only thing I can think of, is I recently updated to Nvidia's 91.31 drivers, which are defective with Half-Life 1 in OpenGL mode, so I used XP's default roll back feature. It was around that time that all of this started. But I've uninstalled the rolled back drivers, cleaned my drives (with Driver Cleaner,) and re-installed the 84.21 drivers again. 'dxdiag' shows no problems, either. And, I've monitored my video card temperatures, and in no way is it overheating.

I guess that's really all the information I can give you about what I know of the problem. Here's my specs and a screenshot:

Gigabyte GA-K8U Motherboard
AMD Sempron 2800+ 1.6GHZ
1024MB DDR3 RAM
Nvidia 6600GT 128MB AGP8x
Realtek AC97 Onboard Audio
Windows XP SP2

Anything else needed? Please ask.

http://img230.imageshack.us/img230/5520/scramblefn5.th.jpg (http://img230.imageshack.us/my.php?image=scramblefn5.jpg)

[SSX21]

Have you changed your video drives since the last time you had the valve software working without any problems? I have had problems with the newer Nvidia drivers causing HL2 to crash when I try to start it and had to revert to older driver to make it work.

[gemstone]

I am yet to experience any problems with 91.31 and HL2 have you seen anything regarding what the problems are ?

[ohtheknives]

Half-Life 2 runs fine with 91.31. I play some Half-Life (the original) modifications also, and with 91.31 drivers Half-Life has problems with black textures over anything transparent if you're running OpenGL.

I've not really had any problems with games or anything or else I would have posted in the video card section. It's just the odd scrambling that "randomly" happens at what seems to be certain times when something is opened.

I have, however, noticed that if I play Half-Life 2 after the screen "scrambles" a lot of triangles are completly black. Again, won't go away until I restart my computer.

It scrambles most of my system tray icons, and when I minimize/maximize windows it has an odd ghosting effect, as seen in the screenshot. The windows will leave squares and reminants of the windows maximized.

Anyway... that's again a lot of what I can think to describe. Thanks for the input, though!

[Platypus]

Is there any chance you could test the card in another computer for a while, to eliminate the possibility of having a faulty video memory chip? And the video card isn't overclocked is it?

Otherwise I'd wonder if there's a problem somewhere with the AGP - I notice there's a fairly recent chipset driver update:

http://www.gigabyte.com.tw/Support/Motherboard/Driver_Model.aspx?ProductID=1876

are yours up to this version?

Also, are there any of the more exotic AGP options like Sideband Addressing or Fast Writes enabled for the AGP in the BIOS? If so it's worth trying with them not enabled, sometimes they can provoke odd problems.

Oh, and, welcome to WinDrivers!

[ohtheknives]

I don't think I'd be able to test the card in another computer. The only other one I can think of only has 256MB of old old memory and it can barely run XP, but my father insists he has it. Heh. I somehow don't think the card would be able to achieve much performance. :P

Thanks for noticing the new chipset drivers, though. I'll install them as soon as I can. I actually had a bunch of problems with this computer until Gigabyte finally decided to update their chipset drivers a few months back (I'm thinking 03/06). I bought the card/computer in October '05, and up until about March '06, because of Gigabyte's chipset drivers, I wasn't even able to use it very well. For some reason the AGP8x card was reading as a "PCIx0" bus. After they finally released new chipset drivers and it actually read the bus right, I went from barely being able to run Battlefield 2 at all @ 800x600 with low settings, I could run it on medium/high settings @ 1024x768 flawlessly.

I personally don't see it being the cause, being that I've been running everything the exact same for quite a while and have never had this problem up until a few weeks ago. But who knows, computers can be really picky! Heh.

RivaTuner tells me that sideband addressing is on, and fast writes is off. Oddly, I've been problem-free ever since I posted this, but if it does decide to rear it's head again, I'll turn this off and see if that has any effect.

Again, thanks for the input, and the welcome! :)