M-Audio Delta 24/96, has upto date drivers and i think the asio drivers were a part of that software package.
I have uninstalled and reinstalled the drivers several times because i assumed it was a problem with the sound card, given the manifested problems, but even without sound being used the CPU seems to be over taxed.
You should be using The "M-Audio ASIO driver" NOT the general multimedia one. That is Steinbergs driver for cards that don't support ASIO.
Do you have a built-in sound card on your motherboard? if so, have you disabled it?
Also, Are you on XP? and what service pack?
so my next guess is that it is an Athlon 3800+ 