Hi Carnth. As you may know I've switched our GPU rigs to LTC mining on a number of occasions when there was an obvious benefit do doing so. This has helped us maintain a yield that's higher than we'd otherwise have been able to achieve while we awaited our consistently delayed ASIC gear. At this time LTC difficulty is 633 and due to jump over 20% in 16hrs. Some of the original GPUs that the company was founded on are already only marginally profitable as it is. I've replaced worn out stock fans with hideous(but effective) kludges on the 5830 & 6950 and the 6870's fan doesn't sound too perty these days. The 7770's and 6770's(which undervolt and overclock well) should remain profitable for awhile still. The rest of them will not when the necessary computer to keep them chugging along is factored into the equation. They're just not efficient enough for these difficulty levels.

Cheers.