Odd video and audio problems, power supply?

[bassakwrdz]

I have recently built a new system for family use and am having some odd behavior. Graphicsare fine and system runs goodfor normal use but when running Sims2 there is graphic corruption in the form of blue blocks replacing game elemnts, also the monitor sometimes resets as if going in and out of power saving mode. When originaly built this system had a Radeon 7000 that used to run Sims2 fine under Win98, tried a Radeon 7200 I had and same thing. Replaced with a new Gigabyte Radeon 9600 Pro 256 and still have same problem. Have tried all the obvious driver issues, including bios and chipset drivers. My guess is power supply not sufficient but I do not get any error messages. PS is stock unit in cheaper case rated 400 watts. Other strange issue is with TV Wonder, when watching anything with scrolling along bottom of screen, such as CNN or Fox News, the volume level fluctuates eratically.Latest MMC and drivers installed. Could these issues both be power supply? Possibly lame MB?
TIA for any help.
Windows XP Home SP2, Asrock K7S41GX, Sempron 2200, 1 Gig pc2700,Radeon 9600 Pro.

 

[DonNagual]

As you have guessed, it could be a number of things. Have you checked if you are simply overheating?

Try opening up your case and blowing a house fan directly on the guts of your case, then running a graphics intensive game. If this fixes you up, you are simply overheating.

The fact that you have the SAME problem on 3 graphics cards (did I understand you right?) is fishy though....

I'd start with the PSU first, personally. Unless you have another PSU lying around to use as a test, the only way to check is to buy a new one (unless you are an electrician and have a volt meter lying around). If you go that route, be sure to check this thread before buying:

http://www.hardforum.com/showthread.php?t=792566

 

[bassakwrdz]

Yes thats right, same problem on three different cards, in a new (two week old) clean system. The problem is actually a little bit worse now with the Radeon 9600 pro card, and that card shoudnt break a sweat with sims2. Maybe more memory needs even more juice making problem worse? My guess still is PSU but was hoping to get a second opinion before dropping another $100 to see if maybe thats the problem. Thanks for link with PSU info, very helpfull. I was concerned that heat may be an issue, espescially with 9600 pro not having a chipset fan, but figure same problem with three cards makes that a little unlikely. Will give opening up the case a try though, well worth the time to try...