Difference between i7-620m and it's SB equivalent?

[BlueWeasel]

Lenovo is having a massive sale on their current T410 and T510. I'm sure they are clearing out them due to the new Sandy Bridge T420 and T520 laptops coming out in a few weeks.

I'm looking very seriously at a T410 with the i7-620m (2.66Ghz base, 3.33Ghz Turbo, 4MB cache) and switchable graphics (Intel IGP with Nvidia 3100m Optimus). This laptop will not be for gaming but I do occasionally need some low to mid graphics horsepower for work. 90% of the time the Intel graphics will be used.

Currently, the sale prices are right in line with with my budget. I'm getting ready to purchase the i7-620m system, but hesitate a little bit because of the T420 Sandy Bridge systems that are nearly here. However, I figure the price for an equivalent T420 system to the i7-620m will be way more $$$$.

Realistically, what are the primary reasons for passing on the i7-620m system (i7-620m, 4GB DDR3, Nvidia 3100m 512MB, 128MB SSD) for the T420 with Sandy Bridge? Can I expect much better on-board graphic performance with SB?

See my original i5 vs. i7 question here

 

[mnewsham]

http://www.anandtech.com/bench/Product/239?vs=338

Not quite the comparison you are looking for but they are the same system except for the CPU so you can see the PURE CPU difference.

 

[BlueWeasel]

http://www.anandtech.com/bench/Product/239?vs=338

Not quite the comparison you are looking for but they are the same system except for the CPU so you can see the PURE CPU difference.

Thanks, that's a fairly significant difference in the CPU benchmarks. However, can I expect that with the i7-620m? The 620m is a dual-core, not quad.

 

[mnewsham]

Thanks, that's a fairly significant difference in the CPU benchmarks. However, can I expect that with the i7-620m? The 620m is a dual-core, not quad.

The performance increase wont be quite the same but it should scale accordingly.