PSU switch turns on PC?

Kaiju · 15 Apr 2010 at 11:55

Corsair 620HXW
Asus P5N-E Mobo
1x 2GB stick of unbranded RAM
Windows 7 32-bit Ultimate

When I turn on the PSU switch, the computer fans turn on full throttle (100%) but nothing boots. To boot, I then have to turn the PC on via the ATX power button on my case.

Only then will all the fans slow down to their normal boot speed and everything starts up.

Same when switching off. After shuting down Windows, the fans go back to full throttle and I have to turn the system off via the PSU switch. Highly annoying.

So far i've:

Reset CMOS battery.
Change the BIOS, although was running the latest version previously (1406).
Loaded default settings in BIOS.
Changed RAM slots.
Changed RAM with old 1GB sticks.

I am running out of options, although I suspect it's my motherboard slowly dying.

The jumpers for the case switches (bar the power switch, thankfully) don't seem to want to work even though i've followed the manual and tried both ways it could be positioned.

I've also had enough network controller problems that i've had to switch to wireless.

Chevens · 15 Apr 2010 at 13:09

I just posted a thread about this - same thing is happening to me - same PSU. When did this start to happen? for me symptoms started 2 days ago..

Kaiju · 15 Apr 2010 at 16:05

I just checked out your thread, funny eh.

I also have an XFX graphics card too, a 9800GTX+ and a E4300 CPU. Our systems seem quite alike really.

I have had this happening for well over a month now. I've had the system for around two years now.

EsaT · 15 Apr 2010 at 21:51

PSU starts fully only if motherboard gives it signal to start.
So even failure for PSU to give power good signal (probably not problem because then PC wouldn't boot from power button) would already require fault earlier in the chain. And PS ON wire having somehow shorted in PSU would prevent it completely from shutting down.

Chevens · 18 Apr 2010 at 18:07

Kaiju - I thought you would like to know I am pretty sure I have diagnosed this as a PSU problem (we both have a corsair PSU also)

When trying my PSU in another system the same symptoms prevailed - turning on the power at the PSU caused power to go to the machine before pressing the power button on the PC.

For me I can no longer boot at all, I would guess you may find the same sooner or later. I will be sending for a replacement so can't tell if the rest of my system has been damaged yet or not

Kaiju · 18 Apr 2010 at 18:48

Thank you very much Chevens.

I will think about doing an RMA after I see your system is fine with a new PSU or my PSU does in fact die on me.

Ironic how I probably spent the largest premium for a Corsair PSU against all my other components and it's close to being the the first to give up on me.