psu problem?

[fuzzybabybunny]

my desktop just locked up, so i pressed the reset button. everything spins up but before i get anything on the screen everything shuts down, and before everything is done spinning down, it turns back on again, spins up, shuts down, cycle repeats by itself. this cycle has happened on a number of occasions already. i just leave my computer off for 10 minutes or so and it usually starts back up fine again.

psu is a 700w fortron. system specs are nothing special - q7700, 7900gt, 2 hdds, 1 dvd burner, x-fi, swiftech water pump.

i did replace the psu fan with a quieter one, but i don't think the psu is overheating because the fan's working and the air being blown out of it is only mildly warm. airflow is good.

 

[Lunyone]

My first thought was that your CPU was heating up too fast and so the system automatically would reset itself. Not sure if you messed with the CPU at all, but would be worth checking that it is seated correctly. My other thought is that the mobo has an issue that is causing this power on/off issue. Another thing to double check is your RESET switch. It might be stuck "active" thus creating the on/off issue. You could pull it off of the mobo and then try re-starting the system and see what happens.

 

[Modelworks]

Check the connector on the motherboard for the cpu fan. Some motherboards will shut down if they do not detect a rpm signal from the cpu fan.