Hi Bitweasel, i solved the problem.
Today i got 40 "old" universitycomputers. Every has a NVIDIA 9800 GX2 in it. I bought them with 2 friends for 7000 € and we are interesting into GPU Rainbowtables. We are new in the Rainbowtable-Cryptanalysis and want to improve our skills. Maybe we can help you with your NTLM 8 full US charset if you want our help.
Reaper