Computer turns on and then quickly shuts off

August 29, 2009 at 19:48:20
Specs: Windows XP

The power supply fan and the dvd drive light come on for about 5 seconds and then shut off. The case fan and the processor fan do not run. I disconnected all connections to the power supply, except for the motherboard, and nothing. I ran another working power supply and hard drive combination and still nothing. Any insights?

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August 29, 2009 at 21:34:13

"Compaq 6000Z"

Nine possible specific models Compaq Presario 6000Z Desktop:

Find the product number, xxxxxx-xxx , or the specific model code, e.g. 6ZPXEH , on the label that's on the outside of the case somewhere.

It probably has a ZZ TOP socket A (462 ) mboard with an Athon XPxxxx cpu on it, part number 261671-001, 261671-002, or 261671-004

Open up your case and examine the mboard to see if you have bad capacitors, and/or other findable signs of mboard damage .

This was the original bad capacitor problem - has some example pictures.
History of why the exploding capacitors and which mboard makers were affected:

What to look for, mboard symptoms, example pictures:
Home page that site
- what the problem is caused by
- he says there are STILL bad capacitors on more recent mboards.

Pictures of blown capacitors, other components - power supplies, Athlon cpu's, etc.:

If you see no signs of that....

Check all the connections of the wiring to make sure they are all the way onto their pins and into their sockets, especially the main connector from the power supply. The wires close to the mboard going into the main power connector/socket should be more or less perpendicular to the mboard surface rather than at an angle. Make sure all cards in slots are all the way down in their slots.

If the cpu fan blade does NOT move easily when you turn to spin it with your finger, you can be fairly certain the mboard did not shut down when the cpu got too hot, and the cpu is fried.

The cpu fan probably must be connected to the 3 pin header for the cpu fan and it must have 3 wires, and the cpu fan must spin, otherwise, depending on bios defaults or settings, lots of mboards will shut down in a very short time after the computer is booted to prevent the cpu from frying (or you can connect any other 3 wire fan to test if there's power there at the header , but that doesn't cool the cpu ).

If the cpu fan blade moves easily when you turn to spin it with your finger, there's probably nothing wrong with the cpu fan when it doesn't spin. It's usually easy to remove it from the heatsink and try it in another computer.
If the cpu fan does NOT spin on another computer, the mboard may not have shut down when the cpu got too hot, and the cpu may be fried.

If you manage to get the cpu fan or another cpu fan to spin....

If you HAVE NOT changed which ram you have installed since the computer last worked properly, or in any case....

See response 2 in this - try cleaning the contacts on the ram modules, and making sure the modules are properly seated:

Try booting the computer.

If you DID change which ram you have installed, the ram you installed may be incompatible with the mboard.

If you knowwhich ram you had installed before, try installing ONLY that ram, try the computer.

If you don't know or aren't sure which ram was installed....

It is easy to test for incompatible ram that has caused your mboard to fail to boot.

Make sure you have a speaker or speakers or the equivalent connected to the mboard so you can hear mboard beeps (see your mboard manual if you need to).
Remove the AC power to the case/power supply.
Remove all the ram.
Restore AC power.
Try to boot.
If nothing else is wrong, you will get no video but you will hear a pattern of beeps that indicate no ram is installed, or a ram problem.
E.g. for an Award bios or a bios based on one, that's often a beep of about a half second, silence for a half second, a beep of about a half second, silence for a half second, continuously.

Your system had either a 200 watt or a 235 watt power supply. Sometimes when apower supply malfunctions or fails, it fries the mboard, and a replacement power supply does not result in the system working.

Check the original power supply.
Failing power supplies are common and can cause your symptoms.
They often partially work, fans and hard drives may spin, leds may come on, yet you may get no video and the mboard will not boot all the way.
See response 4 in this:

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August 31, 2009 at 16:33:09

Thank you for your extensive feedback it was very thorough and helpful. I can't find the product number anywhere on the case, but the model code indicates that it is an AMD 2000+ 1.6g/266.
I examined the motherboard carefully and disovered no bad capacitors or other visual signs of damage. I removed the 6000z case fan and plugged it into my Compaq EVO case fan header and it worked fine. I then removed the cpu fan from the 6000z and plugged it into the EVO case fan header and it worked for about 4 seconds and the system shut down. I had to unplug/plug 120AC to start it again and this time the fan didn't work, in fact upon reconnecting the EVO case fan to its header now the EVO shuts down within 4 seconds of start up? The only difference is all the fans run for the 4 sec. on the EVO. I then proceeded to plug another working cpu fan into the 6000z, neither the case fan nor that cpu fan run but the fan in the power supply stays on and the computer doesn't shut down?

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August 31, 2009 at 18:47:07

The 6000Z system probably has a ZZ TOP socket A (462 ) mboard.
ZZ TOP mboards were made by Mitac for Compaq - lots of older Compaq mboards were made by Mitac - usually there's no model printed on the mboard itself on Mitac OEM only mboards made only for brand name builders, but you may see a PWA...... code printed on the mboard somewhere. I may have more info about the ZZ TOP mboards on my computer somewhere, including which Mitac retail mboard it's the most similar to, possibly a manual or link to one, for the similar model.
NOTE that it probably has oddball wiring for the USB header on the mboard - the Compaq case wiring works with it if it's in it's original case, but other common single piece two row or single row female wiring connectors for front ports on cases etc. probably will NOT.

Many Mitac mboards have no pins on the mboard for a case speaker, or do have unmarked pins on the front panel header but they don't work for a case speaker - you have to connect amplified speakers to the green onboard sound port and the speakers must be powered on in order for you to hear mboard beeps.

The Compaq mboard part number is on a stuck on label on the mboard somewhere, if it hasn't fallen off over time - it often has a bar code on it as well.



261671-002 Motherboard (system board), ZZ Top, for AMD Athlon XP (K7) processors - Does not include processor

261671-004 Motherboard (system board), ZZ Top, for AMD Athlon XP (K7) processors - Does not include processor

".... then removed the cpu fan from the 6000z and plugged it into the EVO case fan header and it worked for about 4 seconds and the system shut down. I had to unplug/plug 120AC to start it again and this time the fan didn't work, in fact upon reconnecting the EVO case fan to its header now the EVO shuts down within 4 seconds of start up? "

That's a situation I haven't heard of before. It sounds like either the 6000Z cpu fan either draws too much current, or the rpm circuit on it may be shorted - probably the latter??

The EVO mboard may have been damaged, but it's possible it's just the EVO's power supply that was damaged - try a used known good power supply with it if you can.

Some el-cheapo PSs, and all better quality ones, have built in anti-short and over-current protection. They won't start up no matter what you try for a short while after the PS experiences a potentially damaging event, then somthing re-sets and it will start up (it may take 15 minutes or more). Usually that doesn't harm a good quality PS, if you have removed or cured the problem that caused the event, but it may harm an el-cheapo PS.

Sounds like either the mboard is fried or the cpu is fried on the 6000Z - in this case it's more likely to be the cpu, because of that cpu fan not spinning for who knows how long, or both may be fried, possibly because the power supply was malfunctioning and damaged them .

If you feel up to the task, remove the heatsink from the cpu on the 6000Z, wipe off the remains of the thermal pad or the thermal grease or thermal compound, and compare what the cpu looks like to the pictures of bad caps and dead Athlons I linked to in response 1 (e.g. a purple or bluish core is not a good thing).
Usually you can't release the cpu socket lever until the heatsink has been removed because you can't get at it otherwise.
However, it may be difficult to get the heatsink to unstick itself from the cpu. Unclip the heatsink clip from the socket - you may need a small screwdriver or similar to help unfasten that - and press down firmly on the heatsink and cpu and try twisting the heatsink back and forth until the bond is broken.

In some cases, if thermal compound was used, it has glued itself to the heatsink like superglue and you can't get the heatsink off the cpu.
I have managed to remove a heatsink plus cpu in that situation by pulling straight up on the heatsink, and doing so didn't damage the cpu socket, but I don't recommend that, and I STILL wasn't able to get the heatsink off the cpu without risking damaging the cpu (e.g. I tried pushing several single edge razor blades like used for some dried paint removing tools between the two - no go -I broke some of the blades).
In that case, you could test the cpu by plugging it into a working socket A mboard system's cpu socket, but you MUST have a working cpu fan on it when you do that.

If the cpu is okay, if you managed to get the heatsink off the cpu, you must scrape off the remains of a thermal pad (straight edges apparent) or remove any hardened thermal compound (e.g. use a single edge razor blade), from the cpu and heatsink, then replace the thermal pad with a new one (difficult to find) or use thermal compound or thermal grease (easy to find) . Thermal compound or thermal grease can be re-used if it's still soft and is clean. I recommend thermal grease because it never hardens (e.g. Silicon thermal grease or Silicon thermal compound, with nothing else in it; translucent, whitish when thicker, almost transparent when in a thin layer).
Cover only the cpu core area.

Whats the brand of the orginal power supply in the 6000Z?
E.g. If it's BESTEC, they are well known to be more likely to malfuction or fail completely, and when they do they are more likely to damage something else - often the mboard, usually not the cpu or the ram.

Sometimes PSs develop bad capacitors, as well - remove it's cover and take a look.

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September 3, 2009 at 18:19:23

OK, I removed the heat sink from the 6000z very easily for it had been set in thermal grease and fell off as soon as the retainer was released. I'm suspicious of the dark spots randomly located on the top surface. They are extremely subtle and I'm not sure if they are signs of damage (hopefully you can identify them). I took a close up photo but this message board doesn't support attachments. If you provide me with a means of sending it to you I will.
You were right about the ps on the EVO, the next day I tried it and it worked fine (must have reset). You were also correct about the ps in the 6000z, it is a Bestec but I put it in the EVO and it worked fine. So basically I'm down to a burnt cpu fan and cpu. My question at this point is do I dare get a new cpu and try it on that mboard, not really knowing the status of the mboard? How risky would that be? I guess I would be willing to change the mboard if it comes to that but I am still having problems identifying it. It has a large logo painted on its surface AM37 and there are three stickers with bar codes: KAL3178472 AM37-L, Lan.ID 0040CA47C984, MAT/NO. 132858.

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September 3, 2009 at 20:37:13

"You were also correct about the ps in the 6000z, it is a Bestec but I put it in the EVO and it worked fine."

In that case the BESTEC hasn't malfunctioned yet, but it's still an iffy power supply. They are usually used in emachine desktop computers and we frequenly hear of them damaging something such that installing ar eplacement power
supply does not get the system working again.

However, that makes it very likely there is nothing wrong with the mboard on the 6000Z, and very likely the cpu is dead - if you get yourself another cpu and cpu fan, your 6000Z system will probably work fine.

You can buy used Athlon XP cpus off the web - if you get the same one it should work for sure.

"....I am still having problems identifying it.'

I've probably already identified it. See the above info - it should have the Compaq part number on it if the label hasn't fallen off. If it is a ZZ TOP board Mitac did not put anything on the OEM only mboard that is of use for you to search with.

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September 3, 2009 at 21:54:18


Some HP EVO info

"It has a large logo painted on its surface AM37......"

Other possible Presario 6000Z mboards...

Compaq name - Actual manufactuer and model - One of the models it was used in

Explorer 2-GL6E - Asus A7N8X-LA - Presario 6000Z

Salsa - FIC AM37 - Presario 6000Z

Mboards used in older HP computers - some also used in Compaqs:

Update 2.

FIC has pages for AM37 but links don't work, no downloads

Pictures and specs:

FIC AM37 was used in some emachines systems

Unofficial FIC AM37 info:

Downloads - the last entry is manuals for two versions of the mboard.
NOTE that there's no guarantee the emachines bios updates there will work with your Compaq bios! They may render the bios useless!

CPU support info, but for the emachines bios versions.

Thoroughbred = 266mhz core Athlon XP cpus
Barton = 333mhz core Athlon XP cpus.

This mboard cannot support 333mhz Athlon XP cpus - they may work but it will run them at multiplier X 266 instead of 333.

The multiplier is fixed, unless you find instructions about how to properly hack the bridges on the bottom of the cpu.

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