PSU problem under load?

I have a 300W PSU. I don't know the manufacture.Some cheap NoName, I think.
The problem started when I installed my GeForce3 card. In some games that require alot from the computer, the computer sometimes reboot or just freezes.

It doesnt mather if I oc or not. My PSU "values" are this under load:
12v->12.46
5v ->4.99
3.3v->3.25
At idle it never goes over 12v or over 3.3.

Could this be the problem?

Btw. Is the Antec 400w quiet?

Those voltages look quite good, are you sure that is under LOAD? 300W is a little weak these days but like I said, those values look strong.

Yes, those voltages are under load. I was running CpuBurn for several hours.

Try using either Toast (High Priority) or Prime95. They should drop very low!

The only diffrence with Prime95 is that I have 12.6 voltage instead of 12.46.

CpuBurn beats all other stressprograms!