Hi,on my laptop-dell xps L502x,everytime I start the computer,I MUST right click on the desktop to get to Nvidea Control Panel,and revert the options to factory install or some such gibberish or I get insane DPC spikes,like 87,000 or something,but once I do that,I get 140,168,never over 200.
If I disable wiFi and the USB 3.0 controller,I get it as low as 20us!,but since I need the USB 3.0 for my external USB3.0 WD HDD,and underside fan,thats a bit impractical,but yeah EVERYTIME I start up I must reinitialize the Nvidea stock settings[even though I have NOT changed,or modified anything!] or spikes to the moon.
This is why I use an ATI card for my desktop,but every interaction is different so,you can't just blanket bag[diss] one brand over another,but the card on my dell[gt540m]certainly has a bag of tricks that plays havoc here!
Good Luck!
Bob