DRAM or M/B error for GA-8I915 Pro (Rev 2.0)

Specs
Operating System: Windows XP Pro
MotherBoard: GA-8I915P Pro(Rev 2.0)
CPU: Pentium 4
Memory: 2x 512 DDR RAM
HDDs: 1 SATA Drive (C: )
2 IDE Drives (not always connected)
CD-RW and DVD-ROM

I've got a GA-8I915P Pro(Rev 2.0) motherboard, and since my computer crashed (about a week ago), it's been beeping.

The first set of beep is 1 long 1 short, which is the code for DRAM or M/B error, and then it does a constant beep with no stopping until i turn the computer off. When it first crashed, it refused to boot up, and just beeped several codes, including the code for CMOS setting error (2 short beeps). I removed one of the RAM sticks from the computer on a hunch and it restarted with the errors "CMOS error" and SYSTEM BOOT DISK NOT FOUND.

I looked in the BIOS, and it wasn't registering my SATA drive, so i hooked up one of my old IDE drives as a slave and it started recognising my SATA drive again (i no longer need to keep the IDE drive in). I then brought a new stick of RAM (512 DDR) and replaced the last stick of RAM with it, but it's still beeping the same code. I now get a message "Press <Ctrl-G> to enter Setup" (which takes me to a RAID menu) or "<Esc> or <S> to continue booting" whenever i boot up.

Would the problem be with the RAM, or with the M/B, and how would i go about fixing it? I'm studying IT at uni and i really need to get my computer going so i can finish my assignments (that were due last week ^_^' ) so any help would be much appreciated