Weird Nvidia driver problems since new HD has been put in

Alright folks, here's a really strange one and I would be most grateful if anyone could shed some light on it.
I have an R1 M17x, 260M SLI, 4gb RAM, quad core Q9000 @2Ghz, Win 7.
On Sunday my HD died. Up til then I was happily playing with (I think!) the 285.62 drivers. BF3, Skyrim etc all playing well. My game of the moment was Dead Space 2, running very smooth.

With the new HD in, first the 285.62 (again, fine before) and the new 295.73 drivers seem to be making the CPU run harder. Going by the CPU meter gadget it's always running at between 20 & 30%, even after a reboot, with very little running in the background.
Dead Space 2 is now very jerky. BF3 is ok but not as good as before.

I went and put the 275.33 drivers on it last night. No initial difference; Dead Space 2 was jerky last night BUT strangely perfect today. Thinking it wasn't the drivers after all (seeing as how it unaccountably improved) I reinstalled the 295.73 (as the 275.33 are out of date for BF3). CPU back to always running at approx 30%.

PCI is off in the BIOS. SLI is enabled. I do a complete uninstall of drivers each time as recommended by experts on this site (incl running CCleaner, deleting Nvidia folder, doing clean install etc).

I have updated drivers on chipset etc. To the best of my knowledge everything is up to date. Win 7 service pack 1 installed today.

Does anybody have any idea what could be happening?

 

Open the task manager, in the Processes tab and trace which process is eating up your CPU cycles.

To you have iTunes? If you do, I bet it's "AppleMobileDeviceService.exe". If so, install the latest Bigfoot Killer Wireless software. Or (IMHO), dump it altogether and install generic Atheros drivers. I've had fewer issues and random disconnects from my wifi router with it. If you insist to keep the Killer Wireless software, also go to the command prompt as adminstrator and type, "netsh winsock reset", and ignore prompts to restore the LSP whenever you run the Killer Wireless Manager program.

If you don't have iTunes and it's not AppleMobileDeviceService.exe sucking up your CPU cycles, then I don't know, sorry.

 

Thanks for the reply. I think I've cracked it. It looks like the Ricoh chipset driver didn't install right. Much better since I re-installed it. Games playing well again.
Thanks again for your help.