I dont often have a problem that i cant work out myself but this one has me stumpted I have a adaptec 72405 raid controller and about 2 months ago it started giving IO errors and raid port reset entries in windows event viewer but the thing is it works fine sometimes not very often mind you also if i dont log into windows the Vms using the raid arrays work fine last time i left it 2 weeks before i logged into windows and it worked fine for another week before i had to reset the system for other reasons then not long after logging into windows task manager shows 100% disk usage on both arrays but 0MBS read write speeds and going anymore that 1 layer deep into the file structure locks up windows explorer i have reinstalled windows a couple of times every time it seems to work for a bit then goes back to doing the same thing i also swapped out the power supply tryed 2 different 2nd hand PSU's i have nothing changed i tried popping acouple of disks of each array out it started fine when i put the disks back in it rebuilt them and worked fine untill i reset the system then went back to the same old problem so im thinking either windows is installing a update that my raid card doesnt like which loads once a user is logged on or all my power supplies are stuffed which i think would be unlikely. Im open to any suggestions as what my problem could be