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.