Stick with the Fatal1ty IMHO. Abit has great support and community help and easy website to deal with.
has the absolute best support I have ever seen, and the Lanparty nf4 is universally agreed to be the best socket 939 PCI-E based motherboard around at the moment. Any record broken on an Athlon 64 will be on a DFI.
And cache size is just clever marketing, RPM is much more important that buffer size in my opinion, and reliability outweighs performance any day in my mind. One should not use a RAID 1 as an excuse for reliability, as the same can be said for any drive.