Very strange Sims 3 error

[herbalfire]

hi there my issue is ive just built a pc for my gf so she can play sims but it shuts out the pc just before the loading screen shows up and I have to clear the cmos to reboot. its deffinatly not an overheating issue because I can play mw3 online for hours on it, any help would be appricated thanks.

system specs are;
pentium d 945
hd 4730 512mb
2gb ddr2
some old hp mobo and a liteon 250w psu out an acer aspire

 

[mailpup]

The power supply might not be adequate. I believe the recommended power supply wattage for the HD 4730 is 450W.

 

[Leeky]

Your power supply is woefully underpowered, to the point where it could potentially place your hardware at risk if it should fail due to overloading.

Whilst a 500w is recommended, AMD list is probably more than necessary, you should at least be using a good, high quality 450w unit.

 

[herbalfire]

thanks guys ill get on to that