If I buy DDR2 RAM chip. Will it fit and run fine in a motherboard that doesn't have DDR2 capabilities?

No it won't.

Will it work? No.

Will it fit? Anything is possible with a pair of pliers and a hammer.... :knock:

The modules are notched every so slightly different.. and they have a different number of pins. So getting it in there wil be quite a bit of work.

But, I remember reading back in 2004 that DDR-2 modules would also be released in 184-pin format.. This is proably because the technology is so embarrasingly simliar to DDR-1, although there would be a somewhat limited compatability. I have not seen such modules yet.

Thank you. That just saved me the trouble of buying one now. Hmm, now to look into buying a new motherboard.

Stupid upgrading.