Ah yes, the resolution is almost certainly going to be different.
Ah Yes, I have a 23'' screen with the Desktop , so the maximum res for the laptop and the desktop is very different . I updated the driver on both machines to the latest version . I have maximized the game and graphic card settings on both machines. the Laptop is distinctively smoother than the desktop.
It could be that the very high rez on the large screen is the down fall for the desktop. I overclocked the HD 5750 abit ( to 800mHz and 1200mhz ) and now it seems to be on par with the laptop.