I ran my own C1 tests yesterday.
The 15.4 2.2 macbook pro compared to my windows 7 desktop I7Quad 3.2 with 24 gigs of ram. The desktop runs an ssd so I worked off of and saved to a 1tb hard drive on the windows machine.
Process 100 1DsmkIII raws to 16 bit tiffs.
Desktop 374 seconds
This was interesting. Usually I can't get anywhere near the times people get on these types of tests, I'm usually significantly on one side or the other. My system is very close to yours though, so I decided to try it:
Win7 x64 Ultimate, i7-950 3.2, 12gigs of 2333, SSD for my system, 2tb WD B where the files were located, another 2tb WD black where the output files were deposited. I didn't reboot, was watching my slingbox, browser up with 8 tabs, Outlook, and LR open.. I brought up C1pro 6.1.0, selected 100 1ds3 raw files, and set output to 300dpi tiffs with ProPhoto..
370 seconds exactly. I used my Android stop watch function..
So.. pretty close.
Edited to add: I ran this test on my x201s Lenovo
, i7, 8g's RAM, SSD, 12.1" with Intel HD graphics. This time I did reboot, the first time I tried it I forgot it had installed the Microsoft updates and I didn't reboot it yet.. and it was taking forever. Much better after rebooting.
920 seconds. Not bad for a 2.4 pound machine.
The only variation was I used 100 5d2 raws to 16 bit tiffs.. because I already had them on the machine.
It looks like Sandy Bridge brings some significant performance increases. Based on your Sandy Bridge i5 performance I'd guess and your Sandy Bridge i7 performance.. I'd guess a Sandy Bridge in the same machine otherwise would (considering the weak Intel HD graphics) would fall somewhere between the two.. for about a 40% performance increase just for Sandy Bridge.