The idea of a dual core is to be able to run two seperate processes efficiently at the same time rather than one using both - so assuming you are using the Boinc client, then everything is fine

Today, I was on my last 3 units before I do my upload. Decided to look at activity monitor (mac pro) and noticed all 4 cores were crunching even though only 3 units were being crunched. Seemed like 2 cores were working on one unit. Wonder whether letting all cores work on one unit at a time might be more efficient.
Randy

WCG science apps are not multi-threaded, so 2(or more) cores can't work on the same WU. Running 2 WU's simultaneously on a dual core CPU is just as good though and makes full use of the resources.

I'm not familiar with a MAC OS, but in Windows, if you were to crunch 3 WU's on a quad core machine, the task manager would show 2 cores at 100% and the remaining 2 cores at 50%. In reality, cores 1,2 and 3 would be running at 100% and the fourth would be idle. But the task manager CPU monitor reflects resource usage more so than actual core usage. 2 cores at 100% and 2 at 50% is exactly the same resource-wise as 3 cores at 100% and 1 at idle.