pc switching off not heat related

[smokey07894]

hi
my gf's system is an athlon 5200+ with 2gb ram and an ati hd 6870 gpu running at temps of 45-50 cpu and 40 - 45 cpu centigrade that is however as soon as we start a 3d game ie eve online it switches off withing 5 mins but usually instantly what could be causing this given the gpu is new and the thermal is not an issue that was my first thought so replaced the heat sink and case fans to improve cooling ????? i have a psu tester and all channels seem to be ok and ran passes tests with mem test so what could be doing this if it was ram would it not blue screen instead of switch off same with hdd fault and power supplies in my experience either work or dont not intermitant fault ????

 

[getochkn]

psu not being able to supply enough power. when it ramps up to game the video card clocks up, the cpu speed ramps up, and at the point, the system goes from say using 200w to 450w in a few seconds and the psu can't cope with that. i would replacing that with a known working one.

 

[hunter315]

I'm betting on the PSU, that 6870 is wayyyy more power hungry than any GPU on the market was when that 5200+ was made. PSU tests only tell you if the voltages are alright with no load, it cannot tell you if the PSU can actually do what is on its label.

What are the specs on the PSU in there and how old is it?