The server is a DL380 G7 dual socket, hex-core with 64GB of RAM, and is running BIOS version P67, as per the HCL.
I have searched the forums and found the nocheckCPUIDLimit, and have tried that in both places (as per http://communities.vmware.com/message/1573816)
Any help would be much appreciated.
I was able to isntall ESXi 4.1 u1 on the exact same hardware as you.
My server is the SKU without an internal CD/DVD drive bay. I installed from an External CD drive just fine. There was one instance where the CD was not being detected, but re-seating the SAS HDD made it work.
Also see this thread: http://communities.vmware.com/message/1611453#1611453
still having this problem with esx4.1u2. "fatal: not a multiboot kernel" when I pxe boot or from cdrom
I came across the same message when I tried to boot ESXI 4.1 from the wrong .c32 file
are you sure that zour config uses the correct version ?
with esxi 3.5 or 5 you can use safeboot.c32 or mboot.c32 while esxi 4.1 only starts from mboot.c32