Hard disks not starting / turning off

[Alejandro]

Hi, i'm almost going crazy with all the troubles i'm having to get my home built system running in top shape.
This are my specs:

ATX Power Supply 300W L&C
Celeron 1.1 Ghz w/ Power Cooler ~5000 rpm
M/B Soyo 7VBA-133U
384 MB RAM PC133 (1 stick x 128MB Kingston, 1 stick x 256MB Samsung recently added)
Maxtor HD's models 31024H2 (10GB) & 90432D3 (4GB)
LiteOn CDROM 52x

Pine GeForce 2 MX 200 32MB
USB PCI card
ISA Network card

running WinXP Pro

Two days ago there was a quite big storm and i were using my computer with no problems. When i shuted it down i also turned off the rocker switch on the back of my PS, just in case. But last night i went to power it and it won't even boot!! The disks did not start (there was almost no noise, but the leds turned on and kept that way). I were very afraid so i took the cover off to see if all was ok. My CPU cooler is not in a viewable point, so to see it i had to take off the PS and put it aside. Tried again and the system started normally. Tried few times more, kept booting. So i put the PS back, started again and when loading XP the progress bar stopped and i've heard the disks turning off!! Happened again once more. I took the PS out again to see if also the cooler stoped but since then i've had no more trouble. Almost started my system 2000 times more, but nothing. I double checked all power connections (from PS to HD's, to Motherboard, and from case to M/b) but all seemed well. Besides, i've been using this machine without problems for almost 2 weeks now!! The only recent change was the 256MB stick that i added 5 days ago...

As a side problem, i'd like to know why Sisoft Sandra reports that the FSB of my CPU is set higher that it should. As far as i know, this Celeron is 1.1GHz (fixed multiplier of 1.1 and a FSB of 100mhz) but Sandra reports that it's rated 66. It's because of Sandra not supporting this "newer" Celeron?

If anybody has a clue, save me from suicide!

[mjc]

Well, if when you had the power supply out everything booted ok, but when the power supply was screwed into place it wasn't booting, it sounds like a your power supply is shorting to ground.

Look fo a a pinched wire, a screw that is too long or something similar.

[Alejandro]

I've searched for that kind of stuff all over there...nothing abnormal.
Could it be that something inside the power supply is loose and causing the short? It could explain this someway because of the movement...
Could it be the power cable? I'll try replacing it, however, since now the system appears to work normally, this is almost impossible to troubleshoot.
To explain further, the second time it happened the system was loading (after POST) that's when the disks went down, but the screen remained on, also leds, and can't tell if the cooler was because the power supply was screwed in.

[mjc]

Sure sounds like it could be internal to the PSU....trying a new lead can't hurt, either.

PS I'm moving this one to the casae, power, cooling forum....

[Alejandro]

Sorry, when you say lead you mean the 20 pin cable that plugs to the m/b? What i tried to say is that i'll replace the cable that goes from wall to computer...
But since the system did not completely power off, i suspect the problem is with the 12 volts only...although when running normal the voltages readings in Setup > PC Health are good (under 5 percent variations)
I would open the power supply to check the cables are well soldered (i did it time ago and i'm aware of the capacitors risk, so i wouldn't go further) but i'm afraid it will void case warranty by breaking the seal. The problem is that i replaced case & PS once, thinking it was the problem but finally it was the modem (See under "Bad PS?") and i'm afraid they'll not change the parts again.
I also wander if this has something to do with the storm the night before. Could somehow discharge the PS capacitors?
As you see, i have not too much knowledge about that area!

Thanks for the help so far

[Jamie69]

I had EXACTLY the same problem with m computer and i had to get a new motherboard!