Diagnosing Computer Issues - many parts already replaced

September 15, 2004 10:00 AM

Computer fixing frustrations - what to do when you've replaced (pretty much) every part and the problem continues? (more inside)

So, a little while back my little sisters computer started to go on the blink. Every so often it would simply lock up and the screen would stay frozen. Eventually it began to lock up during the bios loading procedure, so I doubt it was a hardware fault. Finally, the computer wouldn't start at all - the fans would all start, but the cd roms didn't seem to have any power unless I removed their ide cables. No vga out either.

Figuring this would probably be a ram problem, I went out and bought a new stick of pc2700 ram (this was an original nforce mobo) to replace the existing ones. Still no joy, so I bought a new integrated mobo, case and power supply.

The problem persisted, so I finally ditched the exising 1700XP processor and heatsink and bought a 2000XP witha new heatsink.

Unfortunately, it still isn't loading into bios - the fans and power supply just whirr away..

The current setup is:
New 256MB pc2700 RAM
New PC Chips mobo (http://www.pcchipsusa.com/prod-m863gv15.asp)
New athlon xp 2000+ (133mhz fsb?)
New case and psu
Old cd, dvd and hd (all of which work with other comp setups fine)

Any ideas what's going wrong?

The only things connected on the mobo are the power, reset and hd led connectors (erm, the arrow pointer is the p part, right?), speaker connector, vcore, power and cpu fan. The ide devices are not connected, but still no bios booting.

Any help would be much appreciated, I'm feeling a dash useless here..

posted by Mossy to Computers & Internet (9 answers total)

hmmmmmm, might want to look at the jumper configurations (if it has jumpers) to make sure nothing is set that would cause failure (i.e. wrong clock speed or ram speed). Most mobos these days are jumperless, though.
posted by Hackworth at 10:14 AM on September 15, 2004

Is there any beeping when it starts up? If so, is it the "normal" beeps or an unusual one (i.e. 1 is normal but now its doing 3)?
posted by jwells at 10:17 AM on September 15, 2004

Sounds like it might be a power problem, but you replaced the PSU. What about the surge protector it's plugged into?

Also, if you switched out the motherboard before replacing the power supply, it's possible that the old PSU (if bad) did damage to the new motherboard.
posted by revgeorge at 10:42 AM on September 15, 2004

What revgeorge said. A computer's an integrated system, and if something went on the blink in one of the peripherals and damaged the old mobo (which is what bios toasting seems to indicate), and you kept that peripheral and plugged it into the new system... well, it's going to fry the new system too.

Personally, I'd look at the CD drives. One of them may have had an internal short that's going around and spiking/frying everything else. (Computers have great surge protection at these days from the *outside*, but internally they're even more vulnerable than they used to be due to smaller circuit sizes and spacing.)

This, of course, is why I periodically replace *everything* in a computer system... relegate the old one to the linux box/scrap heap, and buy everything else new.
posted by SpecialK at 10:57 AM on September 15, 2004

BTW, somewhere on your mobo there should be a jumper or contact point to completely reset the bios. Check your Mobo manual for the procedure. Resetting the bios will tell you whether or not the mobo is fried ... if it doesn't do anything even after resetting, you're toastola.
posted by SpecialK at 10:58 AM on September 15, 2004

When you checked your HD in another machine did you move over your IDE cable? Do you get to the stage where a master disk failure is reported if you have no IDE cables plugged in? You could have a bad cable, I've seen them stop a machine from getting past the video boot stage. It's not clear from your description if you unplugged your HD at the motherboard or drive.

I'd be leaning towards bad power as well. It is quite possible you had the bad luck to get a DOA P/S. Take the integrated set up you have back to your vendor and have them test it.
posted by Mitheral at 11:02 AM on September 15, 2004

Since you've now replaced your power supply, it might just be that your replacement RAM got fried by your old power supply. Try moving the DIMM to a working compatible computer and see if it's recognized.

On the other hand, DOA power supplies are annoyingly common on el-cheapo cases (but that's a rant for another day). You can test it with a multimeter and some copper wire, but, if you're the guy people with dead computers usually call, do yourself a favor and buy an ATX power supply tester. It's cheap, it's easy and it's got blinking lights; what more could you want? ;)

Another handy gadget is a BIOS POST diagnostic card. It's a little more expensive, but can prove quite valuable in diagnosing dead computers. You can get what the codes mean from the BIOS manufacturer's site, i.e. Phoenix or Amibios, not PC-chips.
posted by boaz at 12:21 PM on September 15, 2004

if you've got bad wiring in your house, unclean power can cause phantom computer problems. I had a friend who had to replace lightbulbs every two weeks because of the crappy power in his apartment, and his computer was pretty pokey until we put a power conditioner on it (surge protectors for the most part aren't really going to do anything for you -- most of them just seem to add extra outlets; ups devices which claim to do power conditioning didn't work for my friend -- we had to end up buying an industrial looking conditioner. $50 or so from fry's. no problems since.)
posted by fishfucker at 1:45 PM on September 15, 2004

Response by poster: Thanks for the suggestions, will try this weekend.
posted by Mossy at 4:41 PM on September 15, 2004