Computer doesn't respond

[Thump553]

Preliminary rant on/ What is it about computers-my snowblower's busted so I spend four hours risking a heart attack and grievous bodily injuty to clear the driveway, only to crawl into my office to find my computer decides today is the day to strike? /rant off

The computer: HP Pavilion a1030n-Pentium4 3.0 GHz, Asus PTGD-LA motherboard, integrated video, LAN & sound; all stock expect replaced DVD burner a few months ago and bumped up the memory to 1-2 GB (I forget) when the computer installed 2 1/4 years ago, WinXP. One hard drive-the standard 200 GB one.

The computer is left running 24/7/365 for the most part, at night it's basically running Folding@Home, incremental backup program and utorrent. Set so it does NOT go into sleep mode.

Problem: computer fans are running but no video signal to monitor. Manually shut it down, left it off for a few minutes, and booted again several times with no luck. Note that I'm not hearing any beeps when I attempt to boot up from a cold start now. Also not getting the Num Lock, etc. lights on the keyboard to light up.

No hardware changes or significant software changes on the computer in several months.

Any suggestions?

Edit: Link to specs: HP a1030n specifications

 

[robisbell]

check to make sure all fans including the video card fan is running. get a multimeter out and check the voltages.

 

[Thump553]

No video card (built in video). My gut feeling is that it is not a power problem.

It's like the computer is going into sleep mode and won't come out-even on a cold restart.

 

[Thump553]

Any ideas at all? I've tried a different monitor, monitor cable, mouse, power cable and keyboard so far without any luck.

 

[Slammy1]

Does the video work in safe mode? I'm assuming not as you've been here for a while. You get the beeps when you restart but not cold start? Here's a quick guide on checking your PSU with a multimeter, you can find any number of guides in Google.

http://www.ultimatepcrepair.com/news/18.html

 

[w00t]

sounds like a memory problem to me

any way you can borrow some memory from another computer to test?

 

[Thump553]

Originally posted by: Slammy1
Does the video work in safe mode? I'm assuming not as you've been here for a while. You get the beeps when you restart but not cold start? Here's a quick guide on checking your PSU with a multimeter, you can find any number of guides in Google.

http://www.ultimatepcrepair.com/news/18.html

No beeps on restart or cold start. Can't get to safe mode because it apparently doesn't go through POST.

 

[Thump553]

An update of what I've done so far to try to diagnose the problem. Each step was one once at a time and then reversed. I used a known good monitor, keyboard and mouse from a different computer throughout.

(1) Swapped CMOS battery with a known good one.

(2) Swapped power supply with a known good one (and more powerful).

(3) Disconnected both DVD drives (IDE cable and power connections).

(4) Disconnected the (sole) SATA hardrive.

(5) There are four memory modules. I tried booting it with only one module installed in slot one, tried all four.

Nothing works. It powers up, the CPU and case fan come on and the hard drive makes the usual initial clunk or two, but no beeps, never get any video signal.

The only thing I can think of that I haven't tried is a video card, but unfortunately the only thing this motherboard will take is a plainjane PCI videocard and I don't have one. I have my doubts if this would help anyways, since it isn't posting I can't get into the bios to disable the onboard video.


I'm thinking it must be something in the motherboard that died, and replacing this motherboard is probably going to be hard. I have a one-use license for MS Office I'd have to spring for that with any replacement computer.

Any ideas or anything I've missed?

 

[jdw2]

Look over your motherboard for bad caps. Here is a link to what a bad caps look like: BadCaps
They are supposed to be flat. Motherboards in the past that have failed on me always had bad caps.

If you don't find any try taking the motherboard out of the case and booting it on top of a cardboard box. Seems unlikely the mobo would be shorted since its been in use for so long but worth a shot.

 

[Thump553]

I looked at the caps. Only one is suspect with a very slight blug, and it doesn't have any discoloration, etc. on it.

I found a place in Hong Kong that is selling the motherboard on Ebay for $125. Pretty high price for a low level, outdated MB but I might still spring for it.

 

[robisbell]

I'd move up, if you're going to spend that for a old motherboard spend it instead on a newer mobo.