For a little project that I was working on, I needed to modify the vmware BIOS slightly. After reading VMware BIOS modification - for Linux users, this turned out to be easier than I thought.

Step 1: Get the BIOS

$ objcopy /usr/lib/vmware/bin/vmware-vmx -O binary -j .bios440 --set-section-flags .bios440=a bios440.rom.Z
$ perl -e 'use Compress::Zlib; my $v; read STDIN, $v, 211638; $v = uncompress($v); print $v;' < bios440.rom.Z > bios440.rom

The value "211638" in this last line is the size of bios440.rom.Z.

Step 2: Modify the BIOS

This is a bit more difficult. I have been told the Phoenix BIOS Editor is pretty expensive. Luckily I knew someone who could make the changes for me.

Step 3: Use the new BIOS

After you changed the BIOS to suit your needs, all that is left to do, is edit your virtual machines .vmx file and append one line:

bios440.filename = "path to your BIOS file"