Computer crashes!

[crazyguy_60]

When I'm playing certain games (Call of duty 2 + 4 and Crysis), my PC that I built can crash. It happens very rarely, with Call of Duty (and too be honest I'm not too bothered about these games) , but it happens A LOT with Crysis. Every twenty minutes my PC crashes whilst playing this game.
I have turned down the quality from the recommended High, down to Medium/High, and now down to Medium. I downloaded ATI's updates and took the side off my computer. It still crashes. I think that when I turned the resolution down, it didn't crash, but it was so terrible I turned it up again from 800 X 600 (out of desperation ) to 1440 X 900 (my current resolution).
Could there be any other issues? Please help me I REALLY want to play Crysis :lol:

 

[crazyguy_60]

PS I have an E8400 and HD 4850, neither of which are overclocked, but have been in the past.

 

[Proximon]

Probably a memory issue. Go in to the BIOS and make sure the memory timings and voltage are set where they are supposed to be.

 

[shortstuff_mt]

Could also be a heat problem. What are your idle and load CPU temps?

After you set the RAM timings as Proximon suggested, I'd download memtest86+ and run it for a few hours to test for RAM errors.

 

[crazyguy_60]

Idle: 37 min - 40 max - 38.5 celcius avg.
Load (Crysis): 49 min - 65 max - 57 celcius av.
I don't know how hot is when it crashes.

 

[jsc]

Does the system run OK when you are running regular 2D apps? Does it crash only during games?

IF so, that is also a sign of an inadequate power supply.

 

[crazyguy_60]

Yep, it's fine with 2D applications, only with 3D games. This is my power supply:
Hiper M-Power 630W, 18 Amps.

 

[crazyguy_60]

I plan on upgrading to an Intel Core 2 Quad Q9400, HD 4870 and a new PSU.
However, if my power supply isn't good enough, I will get that ASAP. Would this be a good choice?
http://www.scan.co.uk/Products/650W-Xigmatek-NRP-MC651-80plus-Easy-Swap-Output-Protection-ATX-12V-V22-EPS-V292-QUAD-SLI-PSU#ProductFeatures

 

[Proximon]

The Hiper is actually 50A on the 12V rails. The 18A refers to overvoltage protection on a specific rail. It's not an awful brand, usually adequate but generally not recommended due to better units available.

Here are a few things you may need to get numbers for your RAM and accurate temps:

CPU-Z
Real Temp
HWMonitor

 

[crazyguy_60]

I used RealTemp to find out CPU temperatures, and ATI Overdrive to find out GPU temperatures (60 degrees idle/70 - 79 degrees under load). My symptons are exactly the same as people with the same problem. I do believe I need a better PSU.

 

[Proximon]

Well, it's certainly not near the load limit for the PSU, but it could have bad V-droop or ripple.

Something like a Corsair 550VX would work well.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139004&Tpk=550VX