PC crashed while playing video games

[poteljito]

Ok, I really need your help people.
For quite some time my PC crashes when playing video games.
When i play games like Half Life 2(and episodes), TF2, Portal, COD4, CS:S everything runs fine. When i play games like Crysis, GTA 4, STALKER:Clear Sky, Bioshock(not windowed mode) my PC crashed after 5-10 minutes and it's been bothering me since i really want to play those games.
The weird thing is that GTA 4 doesn't crash if i have all the settings maxed out. It's similar with Crysis too: the higher the settings are the longer it takes for the game to crash. So i play the games and after a short time the screen goes black with a little green line going horizontally across the screen for half of the second and then the screen shows as if the PC is turned of the little analog/digital sign(as the samsung monitors usually do when no signal). The sound loops like when i get a bsod, and i have to restart my computer manually.

So I've figure that it's not a hardware problem maybe(since it would crashed sooner under higher settings because of overheating or something similar).

My rig:
Intel Core Duo E8500 2x3.17GHz (no oc.)
DFI Lan Party DK P45-T2RS
4GB DDR2 800MHz Mushkin Value Series
ATI Radeon HD4850 Toxic 512MB
HDD WD Caviar 640GB (didn't make partitions)
Mon. Samsung 20''
on
Windows Vista Ultimate x86 with SP1=>DX 10 (or 10.1 not sure)

I already tried to google it but i had no luck.
I'm ready for cooperation.
If someone could help me i would be very very grateful.

 

[FreedomEclipse]

whats the wattage on your power supply?? & also what brand is it you could have a PSU rated to 1000w but that dont mean squat if its unbranded or an unknown brand you payed $10 at the qwikiemart for

 

[poteljito]

It's a Chieftec 550W. I runned the PSU calculator and it seems to be adequate.
Maybe i should go back to XP

 

[mikek75]

What PSU are you using? Have you ran Memtest on your RAM?

 

[FreedomEclipse]

Some PSU calculators are full of crap. I dont belive half the shit it tells me. its always best to 'over compensate' for power rather then having 'just enough' mind you this is just for the PSU & nothing else.

What make/brand is your power supply?

 

[poteljito]

Memtest86? No I will run it overnight tonight. But I don't know i don't think it's the ram that's faulty.

It's a Chieftec PSU. For the calculator matter i tried to add more HDD's and fans and it was still adequate so i think i have enough.

 

[mikek75]

Cheiftec make crappy PSU's, definitely not a quality brand. PSU calculators are pretty much useless too, as they concentrate on overall wattage instead of sustained amperage which is more important.

 

[poteljito]

So should i buy a new PSU? What brands do you recommend? Is there a test for the GPU?

 

[FreedomEclipse]

It's a Chieftec PSU.

theres your problem - Ive heard of Chieftec making cases & maybe a few other things but I doubt their PSU's compare to OCZ's, Antec's & all the other major brands.

 

[FreedomEclipse]

So should i buy a new PSU? What brands do you recommend? Is there a test for the GPU?

http://www.scan.co.uk/Product.aspx?WebProductId=801620 - for the PSU. I think theres a PSU buyers guide somwhere on the forum, I'l try look it up for you.

when you say 'gpu test' im guessing you mean benchmarks??


::EDIT::

heres the PSU guide - http://forums.techpowerup.com/showthread.php?t=39758&highlight=power+supply+guide

 

[poteljito]

Oh then it should be fine. I tried 3D mark06 i think. Well I'll update you on memtest results. Thank you for you're help

 

[FreedomEclipse]

then what should be fine??

 

[poteljito]

The GPU should be fine. At least i hope