Macbook Pro 2007 problem

Hi there,

I have a sick macbook pro (2007).

Basically it wasn't starting, it gets to the apple logo and the spinny icon and just stays there. Also, if I start in target disk mode, it actually crashes the mac that its attached to.

I have tried:
-Booting from CD and fixing the disk using disk utility - says an error and fixes it, still doesn't work.
- Attached a external HDD and cloned the internal HDD. It clones, but errors out on the verifying stage.
- Reinstalling WITHOUT wiping the hard drive, errors out and throws up the installer log EXC_BAD_ADRESS which I know to be a memory error.

Any suggestions WITHOUT wiping, formatting and reinstalling, the only reason i ask is that this is a friends laptop who REALLY needs the data.

Thanks in advance guys

Just tried resetting the PRAM, now the machine is just starting up, (apple logo and spinny icon) then resetting.

Will try RAM combination's now.

Ok, currently I don't have a screwdriver small enough to get to the RAM, which is a pain

*sigh* still havnt got an apropriate screwdriver, but just tried installing after formatting the hdd and the install failed.