Standard Dual Channel PCI IDE Controller causing Hardware Interupts

Hi All,
I've recently noticed I'm getting very high system interupts (50% CPU) with a new system I built, CPU usage is 50% and I've narrowed it down to IDE ATA/ATAPI controllers basically.

I have a DVD drive & IDE drive via two ATA channels, I've disabled both via device manager
just so I can rule them out of the problem. I also have a standard Dual Channel PCI IDE Controller
which if is enabled i get system interupts and as soon as i enable the system interupts disappear.

But wait for it, if I disable the standard Dual Channel PCI IDE Controller, I still get system interupts
and if I enable the Dual Channel PCI IDE Controller the also disappear untill I restart system.

I've checked to see the IDE drive i was using DMA mode and it is, mind you its disabled anyway.
Process Explorer stats hardware interupts and does;t give me much other info.

I've uninstalled all IDE ATA/ATAPI Controllers and let Vista reinstall them on reboot,
but still the system interupts return.

Anyone shed any light on my problem???
See screen grabs here:
http://www.macrevitalise.co.uk/device.jpg
http://www.macrevitalise.co.uk/taskman.jpg

System Spec: GA-MA790FX-DS5 F2 motherboard, 3gb ram, running Vista 64bit
with AMD Athlon™ X2 Dual-Core 6000+