Yesterday I took delivery of a new GTX 260 TOP (216 core edn) from coolamasta for one of my folding rigs, and after testing on it's own in a benching machine last night and all day today, I wanted to get it running alongside another identical card in one of my i7 desktops. I did the usual setup procedure, extending the displays and installing the second GPU client as I have always done, but something is stopping the cards from running properly together. When I start the second GPU client, the first card drops from 8K PPD to 4.5K and the second card hasn't broke 4.5K PPD yet. The SMP client also slows down, going from 33 minutes/frame to over 37 min/frame, and dropping the PPD from 33K to less than 23K. I am running them in an i7 920 equipped machine, the CPU runs at 4.0 GHz and there is 6GB of 2000MHz Corsair Dominator memory installed. I am running the bigadv SMP client on that cpu with the -smp 7 flag. I know that it's either a lack of CPU resources, incorrectly assigned CPU resources or a shortage of RAM that is causing the slowdown, but I don't know which. If it is the CPU resource assignment, how should I set it for the best results? The cards are running on Arctic Cooling HSF's and are overclocked and can produce 9K on some projects, so I want to get them both running and have the whole system at it's "sweet spot" for maximum production capability. Thanks in advance.