anybody got any ideas why my GPU under win7 and XP(ATI 4870x2 ccc 9.12XP\ccc 10.1win7)is being used whenever i run BOINC (6.10.18) when the only project im running is seti@home?

my understanding is there are only 2 projects atm which use the ATI to crunch data
Collatz Conjecture and Milkyway@home and im running neither of these projects.

ive found the FAQ: Nvidia CUDA & ATI Stream (CAL) FAQ which explains amongst other things how to disable the utilisation but surely this shouldnt need to be done if the project im running dosent use the GPU

What is the evidence you're seeing which suggests that the ATI GPU is being used?

GPU utilisation in CCC is showing its running at max speeds 750gpu\900memory rather than the idle 500gpu\500memory which is usualy where it sits when the cards not being used to render 3d processes

first of i thought it was an issue with CCC so reinstalled older versions but that didnt solve the problem. it was only by chance i closed boinc and the GPU speeds dropped straight away to the 2d idle levels, as soon as i opened boinc again the levels jumpped back up

There were reports in the early days that the hardware detection code used in the BOINC client could change speeds like this - nothing to do with projects at all. I'm afraid you'll have to wait for an ATI expert to come along and tell you if the behaviour is different with other ATI drivers or other BOINC versions.