[64 bit] Problems installing Ubuntu on old Dell PowerEdge 800

Hello,
I'm trying to install Ubuntu (64-bit) on an old Dell PowerEdge 800 Server and I'm running into problems. The server only has a CD-Drive (Not DVD) and doesn't seem to support USB-Booting (As far as I can tell). Ubuntu 64-bit is too large to fit onto a normal CD so I'm struggling to find a way to install it.

Any ideas?

Thanks in advance,
Wallace