Question about problem recently built computer

[shadowneo]

I recently ordered the components and built a computer from Scan, it was my first experience with the company and I have to say I am very pleased, delivery was prompt as was customer services help with changing some items.

I am pretty sure that I know what this problem is, and I feel like a bit of a fool, but this is the first time I have built a PC since my athlon XP 1700+ rig "back in the day". I know i'm responsible for any and all problems with the PC and just hoping to get some advice .

The PC component list is as follows:

Core 2 Duo E6420
Gigabyte GA-965GM-S2 Mobo
Corsair TWIN XMS 2GB 4-4-4-12 PC6400 RAM
Samsung 500GB 7200rpm HDD
DVDR/W Drive
X1950GT 512MB
VIsta Home Premium

The PSU powering this is 400w, which I think is the problem as I think it is below what is needed to power all these component properly. I have ordered a 700w XClio PSU which I forgot to order originally, and it should hopefully be here tomorrow, but I just wondered if anyone could confirm that this is a PSU related problem:

The PC runs vista fine, it recognises the card as I have installed the catalyst drivers, and also runs aero, no graphical anomalies or problems at all. The problem is when a game loads up, as soon as any kind of 3D graphics is displayed the screen froze, with multicoloured artifacting/lines/marks on the screen and the PC stopped responding.

I only tried launching a game twice, as if it is a PSU problem its not something I want to keep recreating! The first time was with Star Wars Empire at War and yielded the aformentioned result, the second time was with Homeworld 2 which initially claimed that the card was an "incompatible radeon card" and ran for a second before producing the same result.

[Lucio]

Does sound like an underpowered PSU meaning there's not enough power to the Gfx card. Only problem is you can actually damage the cards doing this sometimes...

[tigerboyce]

see if you can borrow a psu off a friend and id say you should be looking for 500w minimum

If youre buying id get a corsair 520w Best value psu ever and will work a treat with your setup

[nemesiz]

With the specifications stated a 400 Watt Power Supply could be sufficient to run all the components depending on the manufacturer and quality of the unit. A good quality branded PSU (i.e. Enermax, Antec etc) can run above it's rated wattage for a couple of minutes. Although it should be stated that ATI recommend that a minimum of a 450 watt PSU for their X1950GT 512MB with an 28 - 30 amp on a 12 volt line.

A good indication of power useage can be found here:

www.extreme.outervision.com/psucalculator.jsp

Before ordering a brand new PSU it might be advisable to eliminate other plausible reasons for the crash. Currently there are a number of stability issues with the ATi X1950GT / XT series with the Vista Operating System from drivers, to a physical overheating problems. Try uninstalling the catalyst 7.1 - 7.3 drivers, and use the pre-installed drivers that come with Vista. Also make sure there is sufficient cooling for the system, as artifacting and freezing is indicative of a overheating problem.