Hi everyone - really need some help with something that I should be able to sort myself but no amount of forum browsing is helping.

I have just finished building the first of a number of computers made from second hand and randomly collected parts which will form a render farm for autodesk maya. Working on an extremely tight budget I will be using ubuntu and installing maya onto that and just using the backburner to run on the other machines. Now I am having real problems installing ubuntu via USB onto the PC (there is no optical drive). I have a newly formatted 40gig hard drive and have set the boot order in the BIOS to USB first and all I am getting is the bootmgr is missing error.

I have built PCs in the past and successfully installed windows so I am 99% sure that I have my system set-up correctly however there may be some 'trick' I need to do for ubuntu. Would really appreciate your help. I can't afford to buy many copies of windows!