If price is truly a concern but you wouldn't mind buying one used, I'd recommend the Dell Precision M4400 or M4600. If you check on eBay there should be some available with i7-2720QM or better CPUs, a Quadro 2000m GPU, an HDD with a pre-installed Windows 7, 8, or 8.1, and a backlit keyboard for $425 - $550 (before shipping/taxes.)
If you're looking to buy a new laptop you might be looking at a $600+ price range for something with lower specs than that Dell Precision series. :\