This is a follow up thread to the one below, in which my computer suddenly stopped POSTing. The problem was not uncommon for P5K users, so I thought I'd put the solution up in case anyone else has a similar problem.
In case my sig changes, I use the setup as follows:
Asus P5K deluxe WIFI AP (I've seen the problem reported with many varieties of P5K)
Crucial Ballistix 2x1GB PC2-6400
I think thats all thats really relevant
Booted up one day, and no BIOS beeps at all. The fans run up, and the computer just hangs there, no video, and the power and reset buttons unresponsive. This has often happened with others on first boot, but seems to have occured randomly after years of no problems for others as well.
Even when everything is removed, and the MOBO benchtested with just CPU and RAM, the same problem.
Swapping in single sticks of RAM into different sockets doesn't cure it. Neither does a CMOS reset.
Upon removing RAM totally, you get a 'no RAM' bleep code (long, short short, repeated).
The most telling thing is the 'no POST beeps at all, unless you remove RAM, in which case you DO get the no RAM beeps'.
It turns out that P5Ks have problems with PC2-8500 and PC2-6400 RAM chips sometimes. I had read about this when I was researching what mobo to buy, found mine had no problems, and promptly forgot about it.
The key seems to be to get it to boot with some other RAM of lower frequency (I, and most others put in a stick of PC2-5300), and that'll get you the POST needed to access the BIOS settings.
From there, just change the memory settings from AUTO to whatever you need. 800 in my case of course or 1066 if you are using PC2-8500 sticks.
Save, turn it off, put your original RAM chips back in and reboot. Hopefully everything should be dandy again.
Heres a LINK
to the discussion that helped me, but there are several more on t'interweb.
Hope that helps someone at somepoint!