PC Doesn't Power Off

[omgy]

When I shut down my computer, windows will unload, but the devices continue to run (power supply fan, case fans, & hard drives).

I've also had trouble booting with all the HDD's recently. I've never had trouble in the past. It seems like a PSU problem.

What could be causing this?

Specs:
DFI Lanparty Ultra B NF2 Ultra
Coolmax 400W PSU
AMD Athlon XP 2800+ with Zalman 7000Alcu
2x512 MB Corsair XMS Dual Channel
ATI Radeon 9600 PRO with Zalman ZM80D
Audigy 2 ZS
2 SATA HDD
4 PATA HDD
2x120mm Nexus Case Fans


Thanks in advance.
Zach.

 

[jasonlclei]

I had the same problem here.

Do you have a 20 pin PSU connected to a 24 pin mobo via a 20-24pin adapter? That's what I had and it caused incompleted shut downs (system remains on, but monitor turns off). I removed the adapter and it seems to work now, but not too sure since i had just done that 2 days ago and i don't know if the problem will happen again soon.

If you don't have enough power with ur 20 pin connector, you have to get a new 24pin PSU.

Hope this helps

 

[omgy]

I don't have any power adapter. The PSU is 20 pin and so is the motherboard.

Today I tried reconnecting all the HDD's. I discovered it was a problem with one of the power cables.
If I have that one of the power cable connected to any hard drives, the computer will lock up right before it detects any PATA drives.
As soon as I unplug the cable, the computer boots normally.

I'm still not sure why the computer won't fully power off...

 

[jasonlclei]

Ah so the problem is at the HDD power cable.

Well i would guess that the system would sometimes fail to power down with an error like this.

 

[WildHorse]

Double-check your connections to the power-on/off headers on the mobo.

On my DFI mobo, connections that you'd normally think are across from each other are actually side-by-side. At first glance it LOOKS like the hookup ought to be to the pins across from each other. But no.

It'd be very easy mistakenly mis-connect pwer on/off to the mobo pins that are across from each other instead of side-by-side. So check that.