The list of what Intel sells is here:
http://www.intel.com/intel/finance/pricelist/
The supported CPU list is here, but it is missing enough info to
identify exactly what processors are compatible:
http://www.asus.com.tw/support/cpusupport/cpusupport.aspx
Notice how everything except the last three entries, has an FSB of
400 or 533. There are no FSB800 processors listed.
The last three entries in the Asus list for the PC-DL correlate
with the three most expensive MPGA2 packaged Xeon processors.
Those processors are all FSB533 0.13micron (Northwood era)
processors.
There was a raging discussion, about whether the PC-DL could
be tricked into running two processors at FSB800, as the
hypothesis was that the 875 Northbridge could do FSB800 on
a P4C800, so why not on the PC-DL. The thing is, when two
processors are present, the extra electrical load and multidrop
bus, shoot the good electrical properties of the bus to hell.
So, while the FSB on the P4C800 can be pushed to FSB1000 or
even FSB1200 (300MHz CPU clock), you cannot expect miracles
from a dual processor configuration.
This thread is extremely long now, and I don't plan on reading
it. Have a look and see if the participants made any progress
on coaxing FSB800 from the PC-DL. If anyone has managed to get
the new Xeons to work, then it might be worth a gamble. If
you advance to the last page of the thread, it looks like they
have discovered some mods to do to the board, to get more
from it:
http://forums.2cpu.com/showthread.php?threadid=40755
Most people with a board with that much horsepower, usually
opt for a stable conservative configuration. Selecting two
FSB533 processors is the safe thing to do. If you have a lot
of money to spend, then maybe you can reproduce some of the
overclocks in the above thread.
HTH,
Paul