Need some knoledgable advice/information

[Asphix20]

Hey, ok.. have a pretty serious problem here. I'm pretty computer hardware savvy but this one here has got me stumped. So I come here looking for some godly advice from those out there who might have experienced something similar to this. This post will be fairly long and in depth to prevent having to repost more information later on. If I do forget some information please feel free to ask and I'll gladly follow up with the information.



And now on to the problem:

This summer I upgraded my computer and sold my old components to my Dad. He has had nothing but trouble with it, from over heating issues (he loves to cram in as many 5 gig hard drives as he can) to rebooting issues and so on. Just recently ( the past 2 days) he found out that one of his problems was that he was installing norton antivirus right after install.. which is obviously not a good thing to do before you install any drivers/updates to your OS. He went to try and reformat the machine, and upon installing win2k he was getting errors and reboots. After a couple of tries, the computer refused to post period. Just a black screen. No beeps, nothing. If we removed the ram, then the computer would decide to beep.

We noticed that 2 capacitors (below the socket and to the left of the northbridge chip) were bowing on the top, making them look like they were about to pop. My dad tried taking everything out of the computer except a PCI video card, 1x512 stick of ram, and the processor.. and the machine still woudlnt post.

Through messing around, he switched the dip switch on the motherboard to change the bus from 133mhz to 100mhz and now the computer boots fine. He hasnt had a problem, however with the AGP video card in (geforce 4 ti 4600), the computer will again refuse to post.

SO.. this leads us to believe that the motherboard is caput, and that he should upgrade to a new one (we think that the capacitors are damaged and there isnt enough power being supplied to the devices at 133mhz fsb, and with an AGP video card etc. This is confirmed in that in the bios when running 100mhz fsb, a PCI video card, and 1x512 ddr333 the 3.3v is only running at 2.6v.)

But heres the real problem.. and I dont understand nor have I ever experienced this. Throughout all our testing of individual components, trying to single out the problem maker, when my dad unplugged the USB expansion cable (its one of the s-brackets that goes from an empty PCI slot to a plug on the motheboard, and its also important to metion that he forgot to unplug the power cable from the back of the pc at this point) the computer powered on. Well ok, we just passed it off as very odd.. and kept testing other hardware configurations etc etc etc. After he reinstalled win2k again without problems (now with the motherboard running at only 100mhz fsb) He shut down the machine to install his NIC card. Well again he didnt unplug the cable.. after all its just a nic card.. should be able to throw it in real quick (i know its recommended to unplug.. but it isnt absolutely necessary in some cases). Well when he was putting it in, the PCI slot sparked and the computer booted up!! I've never experienced somethign like this. We have checked all the grounds on the motherboard and everything of that sort.. im completely stumped as to how/why that would happen???!!

We are looking at just replacing the motherboard, but before we do that we want to make 100% sure that its the motherboard. If it wasnt acting odd and shooting out sparks and booting up when nowhere near the power button.. we would say ok.. its the motherboard.. but this strange behavior just makes us doubt some things.

Has anyone EVER experienced somethign like this? Can anyone say with any certainty that it is the motherboard (and capacitors) that are shot.. and getting a new motherboard would be recommended? or could it be something else? I tried to be as through as I could with this post, but if you need any more information, please feel free to ask. Below I will post the system specs. Thanks!!

System Specs
---------------

Athlon XP 2100+ 133mhz fsb
Gigabyte GA-7vrxp+ motherboard
1.5 gig ram(3x512mb pc2700, ddr333mhz)
Asus Geforce 4 ti 4600
western digital 100gb hard drive (he has a bunch of smallter 10/5 gig drives but I made him yank them out)

sparkle 300 watt power supply
soundblaster live! Value sound card

And i think thats pretty much it. The case is a skyhawk case.. I forget the model number, but I dont think thats really needed..

Plz let me know what you think.. I apprecaite it!!

 

[Asphix20]

anyone?

 

[o1die]

It's possible the mobo isn't supplying enough voltage at default to run at 133 fsb. I would manually set the cpu vcore and ddram voltage higher, and see if it will run at 133. Cpu vcore should be 1.6-1.65, and ddram at 2.5-2.6. After changing the voltage, check the readings in the bios hardware monitor section, and see how close the readings are. One epox mobo I had was posting at 1.05 volts for a 1.6a p4. It's amazing it worked at all.

 

[Flinx]

<A HREF="http://www.motherboardrepair.com/index.php?sec=images" target="_new">http://www.motherboardrepair.com/index.php?sec=images</A>

I have got one with what looks like one of the toroid coils burned (partially black). It wont support a graphics card in anything but 256 colors. Also one of the Dimm slots won't take memory. Caps look fine though.

I know what you mean about finding the reason for the problem. Any way for you to test the components in another machine to make sure they haven't gone along with the mobo?

Read the "other" section. There is information on PSU's there (Power Supplies). Since your dad want to load this thing up might be worth looking into how much power you need. The powersupply looks adequate but if you have a multimeter might be worth looking into testing it.

The loving are the daring!<P ID="edit"><FONT SIZE=-1><EM>Edited by Flinx on 08/25/03 07:24 PM.</EM></FONT></P>

 

[Crashman]

So far what you've posted is normal. Bad capacitors create or exascorbate power problems. Did you know that your board can be repaired in about 15 minutes by anywone competent with a solder gun?

Yep, even that sparking was normal. Modern computers don't really shut off, turning them off really just puts them into a deep hibernate mode, where many of the circuites remain active. This is what enables remote power, such as WOL, WOR, WOK, etc.

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<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>

 

[jrooster]

I have experienced something similar.I worked on my friends machine,his power supply went out and he replaced it,but was still having problems.After numerous attempts at formatting and reloading XP,it would get to recognizing plug and play and just sit there.I found I could replace his Video card with another, load XP, then put his card back in and it would recognize it and load up just fine.Here's the kicker,like you I plugged his card back in ,forgetting to unplug the M/C,and it started up!!!!!no sparks or anything,it seems to be running OK just couldnt load XP with the card in.I guess there's something wrong with the video card,probably when the PS went it fried something.