Strange problem, is it video?

[Kestryll]

I am having a wierd things occur on my comp and I'm not sure if it is video card related or not.
After my computer has been on for a few hours it starts changing the video output in several ways. The text in my browser starts changing font or becomes bold and overlaps other text, the icons in the browser show as solid black shapes but when you put the cursor on them the color returns for a moment and the web page when you scroll stutters. Also when I start a game the start up moves very slowly and the game play is far from smooth. This is usually on Diablo2 so it's not that intensive. Once I restart the computer it acts normally but the time until it freaks out is shorter.
Does this sound like a video card problem or is something else messing up? This is on the main comptuer in my sig.
Sorry if this doesn't go in this forum but video is my first suspicion so I thought I'd start here.
Thanks!


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Main Comp
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ECS K7S5A
AMD XP1700+
512Mb PC2100
Visiontek G2ti 64mbDDR
Philips Acoustic Edge 5.1
Linksys 10/100 nic
12x DVD
CDR/RW
56x CD-ROM
60Gb maxtor 7200 rpm
Win98se
Fans everywhere!

 

[CJP]

The font changing thing doesn't sound like your card. Your computer might be overheating. Have you tried running it with the case off to see if all the fans are working?

 

[Kestryll]

All the fans are working and Motherboard Monitor shows the temps are not excessive.
I have two 80mm exhaust fans, one 80mm intake fan and a 5 1/2 bay with harddrive cooling fans pulling air in as well. And a Speeze WhisperRock HSF.
I even checked the vid cards fan, it seems to be running as well.

 

[Kestryll]

Bump to top for more opinions.