bnason

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Jul 14, 2006
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My second post on this ;(

My PC won't turn off. It will turn on and run Windows fine, but, whether I shut-down out of Windows or if I just power off from the BIOS, etc., my PC will automatically start up again.

It WILL power down -- but it's powering back up within 2-10 seconds. I don't know why.

My PC was working fine for months until recently when I had to return a RAM stick that was faulty, and formatted/reinstalled Windows. I know have TWO working DIMMs again but it is STILL reseting itself. I also got rid of my old Soundblaster Audigy card and used the audiomax daughter card that came with my aBit A8N mobo. Still would restart. Unplugged the Audiomax card; still restarts!

My specs
A64 4400+ CPU
aBit A8N mobo
G.Skill 2x1gb low latency RAM
74GB Raptor; 250GB Maxtor
eVGA 7800GT SO CE
Antec Smartpower 450W PSU
Samsung DVDRW

Here's what I've eliminated:

1) It's not a network issue. My ethernet is unplugged. All "wakeup" settings in the BIOS and from Windows are turned off.

2) It's not a Virus or spyware (have run countless checks).

3) It's not a Windows install issue (I've reinstalled Windows from a fresh format).

4) It's not a Windows power setting -- I've changed the reg setting that handles this.

5) It's not a cable issue; I've reseated every cable and plug out of the PSU.

I can't think what else it would be. Should I do a new PSU? New mobo? I'm totally clueless and need help! Which one would make sense to try and replace first?
 

dimwhited

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Jun 23, 2006
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mine does that too, i have it set to turn on with ps/2 input, so if my mouse isnt perfectly still, it will turn on.

idk, just a thought
 

joefriday

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Feb 24, 2006
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Seven things come to mind:

1: bios setting

Do you have "restart after power loss" enabled? if so, your mobo's bios could be crappy and keeps thinking that every time you turn off the computer/shutdown that it is experiencing a power loss.

2: Another bios setting:

Do you have "ring on xxxx" or "wake on xxxx" enabled (xxxx stands for numerous things, such as modem, lan, serial, parallel port, keyboard or mouse)? If you do, a slight vibration can move the mouse to boot the computer, or a ring of a telephone will also boot the computer.

3: front panel wiring

Are your front panel wires (the ones for the power switch, hd led, power led, rest switch) housed in a black connector(s) at the mobo header, or are they bare? They (specifically the power switch wires) could be touching each other at the mobo header, constantly making the computer switch on, as if you were pressing the power button (a short in this circuit is not so likely though, as you'd also be experiencing random power offs and shutdowns).


4. The front power switch is stuck in the depressed state.

5. Random, frequent power surges. Not a lot you can do about these, except perhaps to invest in a good, quality surge protector (not the $8 power strip), if you don't have one already. Sometimes a power surge is enough to trigger a computer to boot up.

6: Flaky power supply. If the power supply is self-shorting it could cause a computer to boot.

7. Bad or improperly installed mobo. The circuit tracings on the mobo for the power connector or the front panel header could have shorted, causing a constant self-boot. The same thing can happen if the mobo was installed and a metallic object (ie a stray mobo stand off) inside the case, usually behind the mobo (but I have seen no-boot situations where the culprit was an ill-fitting I/O panel) is touching these circuit paths on the mobo, thereby causing a short, leading to your phantom booting.


These are in order of most likely. Hope that helps.
 

bnason

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Jul 14, 2006
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See my notes below in Italics. I think it HAS to be a bad mobo. I've never liked aBit anyway. Have everything pulled out of my case and am going to buy both a NEW mobo (DFI nforce4) and PSU (Antec 550w). The 550w is sensible anyway; not like it will go bad. The DFI board will be a complete waste of money as socket 939 is at a dead end, but whatever!


1: bios setting --
I've disabled anything that would restart like this (including after power loss -- it's set to power state off).

2: Another bios setting:
See above

3: front panel wiring
I yanked all this out to make sure it wasn't a culprit. I even took the POWER pins off the mobo and used a screwdriver to turn on the PC by touching both of the POWER pins on the mobo. I turned it off the sameway; and even WITHOUT the front panel POWER plugged - it would still start up on it's own.

4. The front power switch is stuck in the depressed state.
See above

5. Random, frequent power surges.
I wouldn't be surprised; my appartment sucks. HOWEVER, I can't imagine I'd get the consistent automatic reboot due to power surges?

6: Flaky power supply. If the power supply is self-shorting it could cause a computer to boot.
Possible?

7. Bad or improperly installed mobo. The circuit tracings on the mobo for the power connector or the front panel header could have shorted, causing a constant self-boot. The same thing can happen if the mobo was installed and a metallic object (ie a stray mobo stand off) inside the case, usually behind the mobo (but I have seen no-boot situations where the culprit was an ill-fitting I/O panel) is touching these circuit paths on the mobo, thereby causing a short, leading to your phantom booting.
Grri