This week GPUgrid have been having some problems. Their work units have been failing. They think its caused by a bug in the cuda compiler/hardware on pre-G200 chipsets. They have developed a work-around.
At the beginning of the week I upgraded all the quaddies with the latest nvidia drivers (185.85). This made all the GPUgrid work promptly fail. Given the project were aware of these issues (other people were also reporting problems) I decided to run Seti cuda work only on these machines. As a consolation I downgraded the i7 to the 182.50 drivers and its running GPUgrid work on its two GTX260's.
BOINC 6.6.28 became the "recommended" version, which is good because I have been running it on all the machines for a couple of weeks now. It still has issues with work-fetch but overall its reasonably reliable.
In order to keep the CPU's busy I have attached 3 of the machines to CPDN (climate prediction). This is because BOINC doesn't get enough CPU work and gets too much GPU work. The smallest CPDN work units take around 5 days straight to complete.