Lag with decent computer?

[xtremenirvana]

our laptop has the same issue

intel core I7
Intel extreme graphics gpu (not sure the stats)
4g ddr3
1tb HD.

Have to turn the settings all the way down and the resolution all the way down.

now my desktop runs with the settings all the way up at the highest res.
intel quad core black edition 3.1 ghz
gtx 560 TI 1g GPU
4g corsair hardcore gaming ram
1tb hd.

The stats arent really all that different, my desktop is even running twin monitors on one GPU and I can play a GPU demanding game and watch a movie on the other screen with zero lag.

anyone have any idea why the laptop has the lag and my desktop doesnt?