The PC's last days?

[Jo The Veteran]

Ok, here it's the problem.
Screen goes black, not responding to mouse or keyborad.
Hard disks seem to stop cause i don't hear anything from them, and also these leds are off.
And lastly the network connections get disconnected. I know this becuase i operate this pc using remote desktop from another machine and when it hapens, a kinda disconnect/lag icon appears in top right corner.
Other than that the pc seems to function normally, fans and leds on (although again the activity in the hd leds is 0) and generally it stays on.
When i push reset everything works again, while power button only works after 5 secs or so (like when the pc has crarshed).
It happened yesterday late at night for the very first time and today morning to noon again (about 9-10 hours later), a few minutes before i send this post.
Any ideas on what this could be?
Is there maybe a new worm/virus out there or does all of this screams "hardware" to you?

Some things to take into consideration:
The pc details are on my "computer details" button.
That pc runs pretty much on 24/7 basis for about 2 to 2.5 years now. I also don't know how much it worked before that, because it's MB, the 1 of 2 RAMS and the 80GB HD are used parts.
That pc just recently recovered due to an oversurge by a lightning that burned down the onboard ethernet controller device, the AC and also an ADSL modem-router and a switch-hub connected to it. I got the AC, router and switch replaced and the pc worked, till now that is.
I'm doing a virus scan right (on demand - in depth analysis) now but i don't expect to find anything cause the scaner works all the time anyway (nod32).

[AlanHK]

That pc just recently recovered due to an oversurge by to a lightning.

That's pretty likely your problem.

I had my PC zapped a while ago. Some things worked, others didn't.

Had it checked out, the power supply was erratic and not supplying enough voltage. Replaced that and it's been good since.

A generic power supply is pretty cheap, about $20, worth a try.

[Slapstick]

Check the fans and clean the dust out. It sounds more like an overheating issue.

[Jo The Veteran]

Both of you, thanks for your quick reply but i'm afraid i've covered both cases.

The power-suply, i refered to it as "AC". My bad actually, in anycase the box that connects to each part inside the pc and gets AC power from the outside has been replaced at day 1 (lightning day). The pc was working erratic so i had to replace it. After the replacement all worked fine.

In the case of the fans well, it's not it. It occured to me that, that might have been the case so i checked the temperature readings. MB was 40 deegres celsious and CPU 50-52. I actually recently installed a brand new cooler kit for the CPU (the Thermaltake sonic tower together with a 12" fan for it and 2 other 12" fans in the front-rear of the tower). Before the replacement the temperatures where about 70 CPU and 50 MB.
So you see, temperature cannot be the factor here. However, if that where the case, then why would it only turn off parts of the pc like the HD, and the Graphics and Network adapters and leave the rest of it on? Wouldn't it be more logicall to shut the whole thing down if overheating?

Either this is an error in the windows software, caused by a viral agent or maybe by another program gonne bad somewhere, or it's a speciffic hardware part not working well. I just don't know what part. That's what i think.

BTW, virus scan is finished and guess what, no viruses anywhere. Also the problem hasn't apeared for a while so it might have been something to do with the electrical network of the room the pc was in, or a temporary power fail of the whole network of my area. Do you think that's possible?

[AlanHK]

Either this is an error in the windows software

Make a Knoppix CD and boot from that and play with it for a while. If the PC is still erratic, you know it's hardware.

[Nelson37]

Electrical problem specifically including bad ground can cause this.

Power surge damaging mobo could most definitely cause this. If it fried the on-board ethernet connector, this is somewhat likely. Living in Southwest Florida, I would replace the board without question or hesitation.

Get yourself an APC surge protector. This purchase would have paid to repair or replace your PC, APC will send you a check. I know this from first-hand experience, I'm the guy who writes the work order to repair surge damage that generates the check, which is used to pay me.

Bad implementation of power-saving could cause this. Disable it.

Your description is of a lock-up or freeze. Description of hard drive condition is inadequate. If you cannot hear rotational noise, use a digital probe (finger) and check for vibration. It may be necessary to remove the drives from the case. LED indicators useless for any practical purpose. Power indicator is all, fan noise is better.

Note that the disconnect of the network card is not really indicating anything other than the PC has froze, which you already know when the mouse and keyboard fail to respond.

Something is causing the lockup. If the drives completely power down, this could be the source.

Solution is fairly simple. Remove all possible devices from PC, complete disconnection. Run the box in BIOS setup screen for twice as long as the longest observed interval between lockups. Add parts till the problem occurs. Remove that single part and test again, cycle this 2 or 3 times, then you have identified the suspect part.

[TimA-C]

Personally I wouldn't rule out the power supply yet. What is the make and power rating of the replacement power supply? (Not all power supplies are the same) Also, is the hard drive making any unusual sounds when it's working? You may have a damaged hard drive after the power surge. Often you'll hear it trying several times to read a damaged section or you may hear odd clicking noises that it never used to make. If so make sure you've backed up everything of importance and think about getting a replacement. Of course, it may not be a hard drive thing at all, but I'd still make sure that everything is backed up. Good Luck.

[Jo The Veteran]

Thank you all. Fortunatelly the problem hasn't shown again for now.
I will try that knoppix thingy nevertheless.
Unfortunatelly i cannot verify some things you guys are asking.

Like the resonance of the HDs or even vibrations from them. I am however pretty sure that there was no activity in them the first time i checked. 0 sound and maybe 0 vibration. I say this because vibration causes sound too, and i heard nothing at that time. My pc is fairly quiet after some modifications i inflicted in it and it was late night and pretty quiet, still i heard nothing. All the leds where on (except of the HD) and the fans where running, yet... silence.

Now you mention it however I DO hear the HD trying to read several times, and when this hapens the pc freezes for about 4-5 secs. This happens every so once in a while and is not related to the surge (it first occured about 1 year ago). Could this be the issue at hand? Other than that the disks work fine.

[Jo The Veteran]

Man, i don't know what that was, but i guess i stoped.
Silly question though. If the pc had entered stand-by mode, would that explain the whole thing? I mean, it entered stand-by (who knows why, windows do these kind of crap sometimes) and then it locked there. Wouldn't that explain it?