Seasonic S12 500W Problems..

[adam3223]

I decided to upgrade my Antec TrueBlue 480W so i bought a Seasonic S12 500W.

Other Spec:
Amd X2 4400
Asus A8N Premium

Installation went fine but when i turn on the pc, it starts for about 1 second then turns off. (i don't even get to the bios boot screen)
So i push the on button again, and does it again. But it lasts a little longer say 2 seconds.
I keep doing this and about the 4th time or so, it turns on, and stays on and goes through the bios and runs fine.

So I turn my pc off from windows. Turn it back on again and i goes staright through no problems. I relax thinking it was just required a 'first use warmup' or someting.

Then I turn my pc off for the night, the next day it does it again - cuts off a few times then runs fine. This has reoccured over 3 days now, and it seems it needs 3/4 attempt to start after its been off for a while.

After that it seems perfect, no crashes in windows, and i've played games and watched dvds, and its been on for at least 10 hours straight at one point.

Does anyone know whats wrong/what i can do?

 

[adam3223]

It did it again today.

1st attempt lasted about 4 seconds and cut off, the 2nd lasted about 1 sceond, the 3rd about 2, and finally on the 4th is booted up normally.

Last night i recorded the volatages for about 2 hours:

+12v, +5, +3.3v had only minor fluctuations which didn't even show up on the graph.

the VCore was fluctuating quite a lot though, im not sure if thats normal?

Can anyone help?
Should in RMA the Seasonic??

 

[adam3223]

Yes, everything worked fine on my old PSU, which only had a 20 pin mobo connection.

My graphics card is Radeon X300 SE. One of the cheapest i could find. I was intending on buying a new PSU so i can get a more powerful gfx card.