Home built computer won't start...

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[ARCHIVED THREAD] - Home built computer won't start...

Posted: 8/2/2005 9:20:37 AM EDT

A couple of weeks ago my home computer died (there was an awful burning smell coming from it). I tried a new power supply, but that didn't do anything. Then I tried a new motherboard, and that didn't do anything either. THEN I tried a new case (with a new power supply) and it still refused to start. When the power switch is pushed, nothing happens. Yesterday I installed a new CPU, and still nothing happens (actually, when the power swich is pushed, the cooling fan (on the case) moves for about 1/10 of a second, and then stops. The case lights flash also for 1/10 of a second, and that's it).

It is an ATX motherboard with an AMD Athlon. What is there that I could be doing wrong? It's not that complicated or hard to put together. Just to be safe, the colored cables (the ones that run from the power switch to the Front Pannel Connector) go on the left and the white ones on the right?

What else is there do here? The only components I'm recycling from the old system are the disk drives, everyting else is brand new.

Posted: 8/2/2005 9:24:33 AM EDT

[#1]

Go to illwillpress.com then click toons..... Third row 5th one over. Tech Suport. That will help you.

Posted: 8/2/2005 9:26:17 AM EDT

[#2]

Did you read the manual?

Most ATX connectors will only go on one way, so as long as you have the connector seated properly, it should work.

Check all your connections, read the manual, it's probably something simple.

Posted: 8/2/2005 9:26:59 AM EDT

[#3]

Dumb question: Did you try a different outlet or even circuit? How about the power cord?
When you say 'new', you mean new out of box with documentation, or just 'different' ?

Will check the thread before dinner.

Posted: 8/2/2005 9:27:00 AM EDT

[#4]

post pics.

Posted: 8/2/2005 9:28:24 AM EDT

[#5]

Could also be a CPU clock error. Check the manual for the correct jumpers you need for the speed proc you are using.

Posted: 8/2/2005 9:29:48 AM EDT

[#6]

Plug the power cord into an outlet.

Posted: 8/2/2005 9:30:42 AM EDT

[#7]

Quoted:
Plug the power cord into an outlet.

Posted: 8/2/2005 9:33:55 AM EDT

[#8]

Quoted:
Could also be a CPU clock error. Check the manual for the correct jumpers you need for the speed proc you are using.

+1 some motherboards are shipped with jumpers in the wrong position.

eta: make sure you have that 12V yellow wire plugged into your motherboard from the power supply.

Posted: 8/2/2005 9:38:30 AM EDT

[#9]

I had the same problem with one of my computers. One of the USB ports was screwed up and would short out a chip on the motherboard resulting in the lovely smell of a frying computer. If you were connecting or disconnecting any USB device check and make sure the are ok. I could easily see the fried chip when I opened the computer and checked the motherboard

Posted: 8/2/2005 9:39:45 AM EDT

[#10]

it is VERY possible the cpu fried. when you swapped the new board the cpu is still dead or fried the new board.

the system will not do anything without a good cpu.

a tip from one who does this for a living.....

when diagnosing power hit like that ALWAYS replace the cpu and board together. you do not have the tools to properly diagnose which is the problem and it will be cheaper than buyin both multiple times doing problem determination.

i seriously doubt you have a power supply problem but you can meter the connector to be sure.

1st VERIFY the cpu fan is working. it if it not up to speed or not sensing properly the system will not start. i would start there.

2nd RESEAT all adapters, memmory and cpu

3rd minimum config. processor no memmory and spearker. if the cpu bus is good you should get a bios beep tone calling out a memmory failure. if you get nothing here replace mother board AND Cpu.

if the system comes up and beeps, power down and add memmory and video. power on and look for bios to complete. then add adapter and drives one by one looking for a failure.

Posted: 8/2/2005 9:43:58 AM EDT

[#11]

Quoted:
Quoted:
Could also be a CPU clock error. Check the manual for the correct jumpers you need for the speed proc you are using.

+1 some motherboards are shipped with jumpers in the wrong position.

eta: make sure you have that 12V yellow wire plugged into your motherboard from the power supply.

highly doubt this is a clocking error. the system should still post before looking at clock speed. the basic post is only looking for a data path it doesn't care if the cpu is functional or not at that point only that cotacts are made.

Posted: 8/2/2005 10:03:49 AM EDT

[#12]

^^^ What he said.

But , I try with just the mobo, cpu/fan and RAM- no add on cards and then see if it will it post.

ETA: did you double check the way that the CPU is seated??? can you see it from the side to make sure it is level????

See if you can get into bios and check the CPU temp... I realize that tough to do if it won't boot at all..

Posted: 8/2/2005 10:08:43 AM EDT

[#13]

as i understand it it's not even completeing a post prior to bios load. My money is on a blown CPU and possible a blown new MB. that or a bad CPU fan.

Posted: 8/2/2005 10:09:38 AM EDT

[#14]

Quoted:
as i understand it it's not even completeing a post prior to bios load. My money is on a blown CPU and possible a blown new MB. that or a bad CPU fan.

sounds like CPU...but what about the smell??? I usually only get that from a bad PS.

Posted: 8/2/2005 10:13:29 AM EDT

[#15]

Pull the cmos battery and put it back in. I went through every fucking thing I could possibly think of when I just built mine like 3 months ago. It would not post and I was like wtf kill me now. My buddy was like pull the cmos battery and I did and bam it worked. I have no idea wtf was wrong, but it worked. Worth a shot for the 20 seconds it takes to do it.

Posted: 8/2/2005 10:13:52 AM EDT

[#16]

That smell was the Magic Smoke escaping from your computer. Once you let the Magic Smoke out of the computer it is very hard to replace. So hard that most people never even try to do it, they just go out and buy a new computer that has the Magic Smoke pre-installed. Good luck finding the Magic Smoke replacement kit !

Posted: 8/2/2005 10:14:54 AM EDT

[#17]

Quoted:
sounds like CPU...but what about the smell??? I usually only get that from a bad PS.

Or fried CPU because the fan was not seated
properly. Toms Hardware did a failure test on
CPUs and an Athlon will fail within a minute
with no fan.

Posted: 8/2/2005 10:17:44 AM EDT

[#18]

Quoted:
Quoted:
as i understand it it's not even completeing a post prior to bios load. My money is on a blown CPU and possible a blown new MB. that or a bad CPU fan.

sounds like CPU...but what about the smell??? I usually only get that from a bad PS.

the smell usually one of 2 things. blown cap on the MB or HV powersupply, or burning laminante from the cpu itself. i've seen damaged cpu that smoked and had little or no external damage. It's also possible the PS shorted and took the cpu/board with it. PS also have a sparkgap to protect over voltage spikes i have seen those clog with dust and spark... generating smoke with no damage. fix the problems as you find them in order of severity.

if the cpu shorted it could have killed the NEW board as well when it was replaced. when my money is involved i replace them as a set every time.

of course the real problem is that he allowed the magic smoke out of the sealed box.

Posted: 8/2/2005 10:18:11 AM EDT

[#19]

Sounds like you let out the magic smoke.

Do NOT replace CPU without replacing motherboard at the same time. One being bad can kill the other.

Posted: 8/2/2005 10:19:03 AM EDT

[#20]

Quoted:
Quoted:
sounds like CPU...but what about the smell??? I usually only get that from a bad PS.

Or fried CPU because the fan was not seated
properly. Toms Hardware did a failure test on
CPUs and an Athlon will fail within a minute
with no fan.

i watched a dell optiplex cpu bust into flames in under 20 seconds.

Posted: 8/2/2005 10:20:56 AM EDT

[#21]

Quoted:
Quoted:
sounds like CPU...but what about the smell??? I usually only get that from a bad PS.

Or fried CPU because the fan was not seated
properly. Toms Hardware did a failure test on
CPUs and an Athlon will fail within a minute
with no fan.

The test I saw, They pulled the fanns off of a running CPU

,
and the CPU's shut down and protected themselves....

They were the hig end FX's and such. Takes a good sized set to pull the fan off a $900 CPU.

Posted: 8/2/2005 10:25:25 AM EDT

[#22]

if there was a "bad smell" it could affect anything in the box. strip the system down to minimum.

you might need to replace the memory, system board, and cpu all at once., and video card and anything pluged in to the board.

Posted: 8/2/2005 10:27:00 AM EDT

[#23]

Did you plug it in?

Posted: 8/2/2005 10:41:59 AM EDT

[#24]

The motherboard only has two jumpers, and those look OK.

Things that are brand new (NEVER used):

Motherboard
CPU
Case
Power supply

I have checked all the cables, it looks OK (I think), but the darned thing still won't come to life

And yes, it has been plugged on to the AC outlet...

Posted: 8/2/2005 10:45:05 AM EDT

[#25]

Are there any extra studs making contact with the back of the board?

ETA: Try to run it out of the case and on the box the mobo came on.

Posted: 8/2/2005 10:54:13 AM EDT

[#26]

Quoted:
Are there any extra studs making contact with the back of the board?

ETA: Try to run it out of the case and on the box the mobo came on.

There might be a couple. I'll try taking the thing off the case and see if it makes any difference.

Posted: 8/2/2005 10:57:08 AM EDT

[#27]

so MB and cpu are NEW and were not run with suspect parts EVER?

if it doesn't boot outside the case try a cpu fan. if it does, one of the mount studs is shorting the board.

Posted: 8/2/2005 10:57:53 AM EDT

[#28]

One thing about smell...A number of new components will give off a crappy smell when new. Power supllies are a major culprit. I had a Giga-Byte board that wouldn't boot like yours. Most boards are jumperless now so I removed the CMOS battery and waited a few. When I popped the battery back in the machine booted just fine. Make sure the capacitors surrounding the CPU socket all have flat tops. If they are bubbled up, they're dead.

Posted: 8/2/2005 10:58:28 AM EDT

[#29]

Checked the CMOS jumper?

Posted: 8/2/2005 10:59:12 AM EDT

[#30]

Quoted:
Go to illwillpress.com then click toons..... Third row 5th one over. Tech Suport. That will help you.

That is a great site. Another afternoon wasted, it's as bad as finding a new good webcomic.

Posted: 8/2/2005 11:12:07 AM EDT

[#31]

CMOS jumper is set at "normal" position.

The motherboard was installed with the old CPU, when that didn't work a new CPU was installed, along with a new (virgin) CPU fan. I'll try it later with the board out of the case, and see if I have a short somewhere.

Posted: 8/2/2005 11:18:54 AM EDT

[#32]

ok let me say this again.....

NEVER EVER EVER use a NEW board with a suspect CPU or a NEW CPU with a suspect board.

move the cmos jumper to clear and power on. move cmos jumper to normal and power up. there is no need to remove the battery if you have a jumper.

if that fails try it again OUTSIDE the frame. MAKE DAME SURE the surface supporting the MB is non conductive <use the MB static bag.

if that fails.... you like have a dead board and or cpu.

BUY NEW board and NEW cpu. DO NOT use either with the old parts.

this is an expensive lesson to learn.

[ARCHIVED THREAD] - Home built computer won't start...

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