A single spin of the fan then nothing

[Sebb]

Well, this is interesting. I've had the PC together for ages (2 years), after I replaced the motherboard. Then suddenly it dies, will start up for a few seconds and dies again. Now it just spins the fans for a fraction of a second and dies. Because it's been stable for years I don't think all my tech specs will make a lot of difference, but it is an AMD K6 500 on an AL9 (MS-5169) ATX mainboard.

There is definitely power at the power supply - I can run the main fan by shorting the green and black wires.

I've tried the power switch on the two mainboard switch locations, and get the same result. I've also tried shorting manually instead of using the switch.

I have disconnected all cards, drives and ram, and get the same result.

The case was pretty full of dust, particularly a pile of very fine dust next to the CPU fan, but I've blown and brushed this all out.

I can see one capacitor that is discolored on top as if something leaked, but this doesn't look fresh.

I did recently put the case into a new desk which restricts air movement - so it might have overheated something?

I did check the obvious jumpers (though I haven't touched one in 2 years, so can't see that this would be the problem).

I'm not v technical, so might have missed something obvious (I got this far by reading this board).

I do want to get a new motherboard soon, but was hoping to do it on my schedule!!

Any help very much appreciated.

Sebb

[BigBlue66]

I can see three possibilities so far. Power supply, processor or motherboard.

The PSU may not have enough juice to start everything up. Takes a lot of juice on the initial boot. Processor could have overheated and fried. Or the motherboard has gone south. If I had to make a list with top priority on down, I would say as originally stated, PSU, CPU or board.

[Jeronimo]

Hi, Sebb, got no answers but more simptoms.
Try pressing y holding yhe reset switch. The CPU Fan start spinning? Well, thats whats happend to me. I´ve posted today, there´s all the story about it.
One thing i did not write on my post: i could solve the problem when i´ve noticed that the only RAM that this machine have it was installed on DIMM 3. So I´ve remove it and put it on DIMM 1. The problem seemed to be gone, but half hour later it appeared again.
Hope to be helpfull.
Good luck

[JUAN DOS]

Sebb,
The power supply is suspect. It predates your K6 mobo, and will not provide enough watts for a new system, so when you upgrade you will have to replace it anyhow. Why not replace it now, and see if the symptoms go bye bye. If it's not the culprit, you have not wasted $.

[Sebb]

Forgot to mention this in my list - yes, pressing and holding the power / reset switch is the only thing gets a response.

It couldn't be a flat mobo battery, could it?

How about a corrupted BIOS - maybe from a virus?

Thanks for the PSU suggestion - you're right, if I need one anyway for an upgrade then why not get it now and see.

Sebb

[Sebb]

Getting closer..... I tested every output on the PSU, and it looked OK. I took out the processor and then tried powering up - success, until smoke started coming from one of the capacitors on the mobo. Ah-ha! Looks like the processor was detecting the problem and shutting it down. Well, I'm not about to try to identify and replace a capacitor, when it may be another failed compnent that is over-driving it. Not when a replacement motherboard for this processor costs $19, including shipping. Even cheaper than a new PSU. The upgrade can come later.

(But now I can get a complete PC from eMachines for $400 - with monitor, a stick in all the bits I want to keep, that is probably more sensible - will have to check the number of PCI slots, HDD slots etc available)

Sebb

[Budfred]

You can buy an eMachine if you would like, but I would urge you to look at other options first. If you want to build your own, you could build a pretty hot system for $400. You can also order a custom system from a number of good web vendors for that amount. With eMachines you will get low quality parts and almost nonexistent support. Check out this thread:

http://www.pcguide.com/vb/showthread.php?s=&threadid=17448

Budfred

[Sebb]

I thought that might get a howl of protest! :) I will have a look at that thread - I didn't think that parts could be put together for $400 - I will look further. And if I do it myself the the level of serivce is zero - given that I always have myself, but with eMachines or HP it's just possible that someone lese might help me too. I used to work for HP - in minicomputers - their service and quality was legendary - shame that's not true of PCs today.

Sebb

[Budfred]

Yeah, I am afraid that HP's quality of service is now becoming legendary for the paucity of it.:(

I am building 3 systems at the moment. One is a 1.3 P$ and one is a 1600+ AMD. Neither will cost me $400 even with the OS included, but I am a bargain hunter, so I have found pretty good deals on almost everything. I know there are a number of systems around for about that price that would provide more than eMachines. A PCWorld article earlier this year said that local mom & pop computer stores were rated higher for their service than any of the big companies and in my area they have a lot of fast cheap systems at those type of stores. Whatever you decide to do, good luck with it...

Budfred

[Budfred]

I forgot to mention earlier, this PCGuide Forum is the best support service I have ever used and it is free. It is generally prompt and almost always provides a solution. That is far more than I can say for any other support service I have ever used.

Budfred;)

[Sebb]

I am amazed by this place - I learned an enormous amount in very little time.

An AMD 1600+ system for $400 sounds great. Off the top of my head I would have thought:

Case and power supply $50
Processor - guess - $130
Mobo - guess - $80
Memory 512 - $50
Drive - $50
Floppy - $20
CD - $40
Monitor 15" 50$ - would be pretty poor quality

$470 and assumes on-board sound and graphics, Lan, modem (not needed). No DVD. If you could get $10 off each componenet then you would be at $400.

I already have the floppy, CD, HDD, monitor, old video card, don't know if my DRAM would work....

[Budfred]

Ok, here's the prices that I can remember for that system:

Motherboard and CPU from NewEgg: about $110
w/onboard sound
Case (from local computer show): $75
Antec TruePower 330watt from MicroCenter on sale: $45
Modem from eBay: $17
ATI Video 64MB from NewEgg: about $35
Maxtor 40gig HD on sale after rebate: $50
Samsung CDRW 40x12x40 on sale after rebate: $30
Old DVD drive: $???
Floppy drive from NewEgg: $13
Cables and fans: about $25
256meg DDR RAM on sale after rebate: $25
WinXP Home full: $90
Total = about $515

This is the most expensive of the 3 systems I am building because it is going to my sister for a present, so I splurged on a few things. It was going to come in under the $400, but I got a more expensive case than I originally planned (with a cool window and all aluminum) and I got a new video card, more expensive OS and new CDRW. I could have knocked the price down by cutting a couple more corners if necessary. The 600mhz AMD system totals more like $250 and the 1.3 P4 will total under $400. I am only talking about the computers here, but you probably already have a usable monitor from your old system, as my sister does. It is also true that I am a bargain hunter and got good prices on most things, but the prices are out there for anyone who wants to find them. It would certainly be less hassle to get an eMachine, but it wouldn't be as much fun!;)

Budfred