Compaq Motherboard problem...

[wan901]

Hey Guys i got some Problem on this PC SF ( Compaq D500 SFF ) the small factor. the problem is sometime it can boot but sometime it can't and even sometime it has RAM slotted (beeping) , and sometimes Failed to Run Memory test . What is the problem is it the Caps or anything other electronic part problem , but i saw a TAEPO or TEAPO capacitor ... is it a problem ??? What I heard this kind of caps had a problem... please help me

[UraBahn]

Re: Compaq Motherboard problem...

Hmmm, what I'd do first is check the power supply. A failing power supply can mimic the effects of bad capacitors on a motherboard; sometimes, power supplies fail because of bad-quality capacitors that blew inside them!

And yes, TEAPO aren't exactly the best of caps to use in motherboards, but they're far and away from being the worst. I'd try to eliminate the power supply as a potential problem first.

[toastygoodness]

Re: Compaq Motherboard problem...

knowing HPs the power supply should be the first to replace, as it is a Bestec. actually, you better replace that before it burns down the whole motherboard. the sad thing is that even their business (HP Compaq) computers have started to use Bestecs. That's also a SFF, so it might be hard to find a replacement for.

[wan901]

Re: Compaq Motherboard problem...

Guys ...id change all the caps ...but now i heard some noisy thing came out from ther power supply (rellay ticking sound..) do you the Psu ??

[shadow]

Re: Compaq Motherboard problem...

Well it could be. You should open up the power supply and have a look....post a picture here. The ticking noise could be an inductor ringing, a capacitor ringing and just a very bad fan. In any case, opening it up and inspecting it will not hurt. Just make sure you inspect it when it is turned off!

[wan901]

Re: Compaq Motherboard problem...

GuyS,.. Here the PiC of the D500SF power Supply..... im thinking the sound tiking is the 2pin Relay (blue colour one) got two there .... and the bad news is the mobo not posting (of course changed Caps already) still not posting and no beeping ..... and some tiking sounds from PSU ....i suspect the PSU ...how bout ur guys ?? here some of the pic of the PSU

[starfury1]

Re: Compaq Motherboard problem...

well no idea really on that psu
but they look like mains rated capacitors to me (x or y can never remember position)

The ticking sound sounds to me like the psu is trying to start but can't fire up due to a fault
what the exact faulty component might be I have not real idea


Further.... since you have recapped check you have no shorts on psu rails this could be causing the PSU to shut its self down

I take it this is your MB Here

The three large ones are probably the on board Voltage Regulator (known as VRM)
Input caps the 10 (I think you said) are the output filter caps these should be low ESR types
the other two would probably be general purpose Electros

The behavior first posted is typical of bad caps or a failing supply caps
but its by no means the only cause

I suspect a problem with your recap at this point, causing the psu to shutdown
please recheck your solder work, cap placement and look for any solder Bridges
or solder splatter on the pcb.
A mag glass is very helpful here

lastly what caps did you use were? Thanks

There are others that would be more familiar with these MB and PSU then I

[wan901]

Re: Compaq Motherboard problem...

Hmm i checked several time already ...i tried the psu without plugged to the mobo (just plugged the psu) i heard something ringing or maybe fast ticking (just like realy ticking) .....

[wan901]

Re: Compaq Motherboard problem...

Oh yeah... i'd change the new caps on those three caps (1000uf 25V) with the rubycon one........still doesn't posting....what i afraid the psu got a problem cause i heard ticking sound came out from rellay or maybe the big Caps ....(tried without mobo)

[wan901]

Re: Compaq Motherboard problem...

Ok Guys i tell step by step what i did...First My friend gimme the PC to install Vista ....and i install it ....it seems to be okay no problem.....later ,tommorow i started the pc and i get not posting , what im thinking is remove all the component and put it back...and yes its posting ...after that i shut down for 4 hours and then i boot it back it became not posting again....then i remove the ram it post ,but memory test fail....then i reconnect the ram...its beeping sound (RAM not availaible, 3 beeps) then after its ok ....(weird uh ..) then after a few hour.... i restart (cause installed a driver) then it became back not posting at all...after i tried to do what did i do before its still not posting....then i change the 10caps still the same ,change the 3 caps 1000uf 25V still same, change the 1000uF 10v still the same (not posting at all) and no beep, then heard very fast ticking sound came out from psu ( without plugged into the mobo) then suspect PSU ....and just now when i plugged into the mobo (its had ligth at the mobo ) but cannot started or turn on either.... now i really suspect the PSU problem.... :-(