[spunk.funk]

doesnt progress any further than the Gigabyte utilities splash screen. I cannot open the CD drive

This signifies a hardware problem. When you power up the computer can you press the eject button for the CD drive? Does the tray open? Does the light on the CD drive light or blink? on the Gigabyte screen can you enter Setup (Bios) usually by pressing the Del key?
If not, then shut down the computer and unplug all drives (CD/DVD, HDD's, Floppy etc) and start the computer. Can you get into the Bios? If not, then you may have a failing Power Supply Unit. Try testing with another.

 

[spunk.funk]

can you enter Setup (Bios).....Usually, yes.

If you can boot into Setup (Bios) On the first page, do you see your CD/DVD rom drive listed? Do you see your HDD Listed? Have you unplugged the CD/DVD drive and try to start the computer?

 

[spunk.funk]

Try plugging in the CD/DVD drives power plug to the drive, do not plug in the Data cable in. Start the computer. Try to eject the tray, if that fails, then this drive needs to be replaced. If it works, shut down the computer and re-attach the data cable. Start the computer, try the tray again, If this fails the drive needs to be replaced. If this succeeds, the data cable may have been loose.