I too ended up with the same problem - that is - unable to get into the BIOS.
I had problems with the OCZ PC3200 Dual Channel Optimized RAM - so I bought 2 sticks of Crucial PC3200. The RAM settings were set at 3.0-3-3 and the Crucial worked like a charm. Changed the "Performance Mode" to "Standard" and the Crucial hummed right along. MemTest-86 found no errors and I enjoyed a bandwidth of 2186 unbuffered (4700 buffered). Which isn't shabby.
Now to try setting "Performance Mode" to "Turbo". This is when all hell broke loose. Dead machine. Unable to get into the BIOS. Tried everything - running on 1 stick of RAM, clearing the BIOS manually - to no avail (had BIOS version 1010 Beta at that time).
Now I didn't know about the "Insert" key. But "Delete" sure didn't get me in.
What got me into the BIOS was replacing the Crucial CAS-3 with one of the defective OCZ CAS-2 sticks! Voila! Up and running. Filled in the time, date, etc. (so the clear had worked) - and set the RAM timing to 3.0-3-3 for the Crucial. Turned the machine off & plugged in the 2 sticks of Crucial - all happy again.
However, since I no longer have the 2 sticks of defective OCZ, I am somewhat leery to try to go for that last bit of performance out of the Crucial RAM. Still running with "Performance Mode" "Standard".
I reported the problem to ASUS. What a waste of time. No reply since August 5th.
P.S. I would strongly advise anyone to run MemTest-86 before installing an operating system - for multiple loops. My OCZ became faulty on average 1 in 6 passes - at the high end of the RAM.
I used to swear by Windows 98SE - until I tried Windows XP. I am after STABILITY and PERFORMANCE - in that order of priority. With the P4P800 Deluxe, P4 2.4C and Windows XP - I have just that (unfortunately still with CAS-3 Crucial). I am now on my 3rd set of OCZ PC3200 Dual Channel Optimized RAM and hopefully when this one arrives, it will be flawless.
Otherwise, another RMA - this time directly to OCZ in the USA. To date I'm out $25 in shipping charges & still have no working OCZ.