My Brah's Computer Problem

[Der-PC-Mann]

OK, so, I'm not in the same city as my brah, so I cannot have a look at his computer to try and fix it, and besides which, he's pretty damn good with computers as well, so I doubt I could do much that he hasn't already done.

Problem: His computer won't turn on; won't even post.

He gets NO beeps. His fans do work, which suggests the motherboard is getting power, but he says that one of this molex (the usual 4-pin molex) fan isn't spinning, which suggests a problem with the PSU, however, he has tried another 400w PSU and says the PC still won't turn on. His rig has been working for quite some time without any problems, although he did mention (I wish he has said this before, so I could tell him to replace the PSU. ) that his PSU would sometimes "cut out"; not quite sure of the specifics.

This is a computer built by someone with several years of hardware experience, with mostly brand new parts. I suggested to him that he unplugs EVERTHING but the motherboard and CPU, then plugs them in one by one to find what might be causing a problem, but sadly he's already tried this, and the PC still wouldn't do anything, even with just the motherboard and CPU.

PLEASE any help would be appreciated. He loves that PC, and is really gutted about it going kaput. Any diagnostic measures you can suggest that he or I have overlooked, please suggest away.

 

[Celegorm]

When I see this happen, it's usually motherboard or PSU related. Being that a new PSU has been tried, I'd be willing to bet that the motherboard is dead. To confirm, he could take out all of his RAM. If the motherboard has any life left in it, it'll beep like crazy to indicate that there is no RAM in the system.

 

[OhSnapWord]

Stupid question.

Is there a case speaker hooked up?

I ask because a lot of newer boards and cases no longer come with this speaker. If this speaker is absent, there will be no beeps.

 

[Der-PC-Mann]

Yeah, that was my thinking. I asked him and he said that it did the same thing: no beeps. :| Guessing it's looking a lot like the motherboard is ******, which is odd, since it's brand new. After asking him several more questions, I've discovered the following:

His 4-pin CPU connector is what was causing the PSU "cut outs" he assuredly believes.

He's changed the BIOS battery (not that it's likely to work) and not too surprisingly, it didn't fix anything.

He's checked for blown capacitors, to no avail.

He's checked for any short circuit issues, to no avail.

Apparently the North Bridge "gets warm".

He has taken the entire motherboard out and had a good look at it, but no sign of damage.

The 400w PSU he tried did have a 4-pin CPU cable, as I suspected it may not have, so that's not it.

 

[Der-PC-Mann]

Yeah, there is a speaker.. it's not the usual kind, it's one of those lil tiny speakers attached via the the short wire; I have one in mine, that came with my 990FX motherboard, and no problems with it: beeps just fine. He was also getting beeps, prior to this problem. (normal beeps)

 

[OhSnapWord]

What board is he using? Did he test with a known good PSU?

 

[Der-PC-Mann]

He tested with another PSU that he has successfully used before. Neither PSUs are that fantastic; his 400w PSU is just a generic old thing, and the 650w PSU he's currently using (and has used for a while) is just a generic cheap Alpine one, although not too bad, it's not one you'd wanna stake your life on.

 

[Celegorm]

With everything else being tried already, we're pretty much down to a bad motherboard or bad CPU. In my years working at the shop I've only seen one CPU go bad that wasn't because someone forced it in the socket wrong so I'm willing to bet that the board is dead. If it's under warranty I'd try to replace it. If it's not under warranty and he has another CPU of that same socket laying around I'd try putting that in just for kicks before spending money on a new board.

 

[Der-PC-Mann]

Yeah, thanks for the posts, guys, it's mucho appreciated. Looks like he's going to try replacing the motherboard and/or CPU; I think it's just the motherboard, as well. It's such a shame.. is his first sweet rig that he's been able to pay for and build. Sucks when tech kicks us in the nads.

 

[~Darkseeker~]

OF course it won't POST with just mobo and CPU!! xD PC Needs memory to function at all, with none installed it won't turn on past the BIOS anyway.

In my experience this is usually memory or GPU, buy some cheapo compatible memory and put it in, see if it works.