Motherboard will not POST

T

Tom Mislewski

I'm building a HTPC with a Pentium 4 3.2ghz Northwood CPU, two 512meg
sticks of Mushkin PC3200 ram, Zalman CNPS 7000-A AlCu heatsink, Arctic
Silver Ceramique thermal compound, and a Intel 865 PERL motherboard. The
power supply I'm using is a 400w Seasonic Super Silencer. When I 1st
powered the computer the heatsink fan started up and I got a very rapid
series of beeps. I thought the problem might be caused by CPU as the
Intel 865 PERL instruction manual stated that seven beeps indicates a
CPU problem though there seemed to be more than seven beeps sounded in
the attempt to boot.

So I removed the motherboard and power supply from the case, removed the
heatsink and CPU, cleaned off the old thermal compound with 91%
isopropyl alcohol and reapplied a new coat os thermal compound. I also
removed and reinstalled the two sticks of Mushkin RAM. I left the
motherboard out of the case, jumpered the off/on pins on the motherboard
and reconnected the power cables.

Now when I try to boot the system I no longer get any beeps. Instead
after about 5-7 seconds the fan on the heatsink stops spinning. I've
tried attaching a video card but the machine never gets far enough along
to output video. Any idea as to what's wrong. I hope I havent fried by
motherboard or CPU. Thanks.
 
K

kony

I'm building a HTPC with a Pentium 4 3.2ghz Northwood CPU, two 512meg
sticks of Mushkin PC3200 ram, Zalman CNPS 7000-A AlCu heatsink, Arctic
Silver Ceramique thermal compound, and a Intel 865 PERL motherboard.

You do realize that a 3.2 GHz CPU is a bit excessive?
It'd be good to undervolt and underclock it.


The
power supply I'm using is a 400w Seasonic Super Silencer. When I 1st
powered the computer the heatsink fan started up and I got a very rapid
series of beeps. I thought the problem might be caused by CPU as the
Intel 865 PERL instruction manual stated that seven beeps indicates a
CPU problem though there seemed to be more than seven beeps sounded in
the attempt to boot.

First thing I'd have done is checked for any motherboard
jumpers, cleared the CMOS, and removed one memory module.

Then again, i have no idea of any or all of these parts are
(yet) proven working, new/old/etc/etc, would be making
certain assumptions.

So I removed the motherboard and power supply from the case, removed the
heatsink and CPU, cleaned off the old thermal compound with 91%
isopropyl alcohol and reapplied a new coat os thermal compound.

It's not sitting on an antistatic mat or packing material,
is it? I ask because it shouldn't be.

I also
removed and reinstalled the two sticks of Mushkin RAM. I left the
motherboard out of the case, jumpered the off/on pins on the motherboard
and reconnected the power cables.

Don't jumper the off/on pins, because, well you'll mention
it in a moment...

Now when I try to boot the system I no longer get any beeps. Instead
after about 5-7 seconds the fan on the heatsink stops spinning.

How do you "try to boot"?
It ought to turn on immedately after plugging the AC cord
into the power supply, if as mentioned above you had
jumpered the PS-On pins, but then because they're jumpered,
it'd turn back off again in a few seconds- because the pins
need be a momentary contact, just touch something (or the
jumper) to short them for an instant then remove that
shorting part.

I've
tried attaching a video card but the machine never gets far enough along
to output video.

???

Attaching a video card or a monitor?
It needs a video card, always..
Set it up in a bare minimal configuration with ONLY:

Video card, 1 memory module, CPU, CPU heatsink/fan, fan
plugged into CPU fan header on the motherboard. If your fan
doesn't have RPM signal (3rd lead output), substitute a fan
that does if it doesn't work "yet" otherwise.

Naturally you'd connect the monitor to the video card. You
do not need keyboard, mouse, drives, nor any case connectors
yet. Momentarily short the two Power-on pins together with
anything conductive, for a brief moment. At that point the
system should turn on and run... until you short the two
power on pins together for about 4 or 5 continuous seconds,
or touch it again momentarily (depending on which option is
set as the default in the motherboard bios.

If it works at that point, proceed to hook up keyboard and
check bios settings (if applicable). If that works and it
completes at least a couple off/on cycles, try recasing it.

Any idea as to what's wrong. I hope I havent fried by
motherboard or CPU. Thanks.

You haven't mentioned anything to indicate that may've
happened "yet".
 
T

Tom Mislewski

It's not sitting on an antistatic mat or packing material,
is it? I ask because it shouldn't be.

Yes it was sitting on the antistatic packing material. Big mistake on my
part.

I also
removed and reinstalled the two sticks of Mushkin RAM. I left the
motherboard out of the case, jumpered the off/on pins on the motherboard
and reconnected the power cables.
Don't jumper the off/on pins, because, well you'll mention
it in a moment...

Another big mistake on my part.
Now when I try to boot the system I no longer get any beeps. Instead
after about 5-7 seconds the fan on the heatsink stops spinning.
How do you "try to boot"?
It ought to turn on immedately after plugging the AC cord
into the power supply, if as mentioned above you had
jumpered the PS-On pins, but then because they're jumpered,
it'd turn back off again in a few seconds- because the pins
need be a momentary contact, just touch something (or the
jumper) to short them for an instant then remove that
shorting part.

I removed the jumper from the on/off pins and the motherboard booted.
Thanks for all your help, Kony.
 

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