debugging a dead p4p800

[Doug]

Last night I installed some more memory in my p4p800. It didn't boot
after that. So I put back the old memory. Still didn't boot. No bios
info on screen. When I turn on the switch, the cpu fan comes on and I
hear some movement of my harddrive then nothing. Screen completely
blank.
I tried the graphics card in another computer - ok. I replaced the
power supply - no go. Couldn't try the sata hard drives on the other
system since it has parallel ide drives.
I removed the battery and discharged the battery backup memory power.
No diff.

Any ideas of what else I should try?

 

[Rod Speed]

Last night I installed some more memory in my p4p800. It didn't boot
after that. So I put back the old memory. Still didn't boot. No
bios info on screen. When I turn on the switch, the cpu fan comes on
and I hear some movement of my harddrive then nothing. Screen
completely blank.
I tried the graphics card in another computer - ok. I replaced the
power supply - no go. Couldn't try the sata hard drives on the other
system since it has parallel ide drives.

I removed the battery and discharged the battery backup memory power.
No diff.

Any ideas of what else I should try?

You have to have the system unplugged for a while before discharging the backup battery.

 

[Rod Speed]

You have to have the system unplugged for a while before discharging
the backup battery.

Its possible to kill a motherboard by changing the ram, particularly if the
memory is tight in the memory slots and the board isnt properly supported
under the memory sockets. You can flex the board bad enough to kill it.

 

[JAD]

Last night I installed some more memory in my p4p800. It didn't boot
after that. So I put back the old memory. Still didn't boot. No bios
info on screen. When I turn on the switch, the cpu fan comes on and I
hear some movement of my harddrive then nothing. Screen completely
blank.
I tried the graphics card in another computer - ok. I replaced the
power supply - no go. Couldn't try the sata hard drives on the other
system since it has parallel ide drives.
I removed the battery and discharged the battery backup memory power.
No diff.

Any ideas of what else I should try?

as RS said and a good cmos clear results in a checksum error at boot.