I ran a benchmark on my computer and my friend's.

I'm going to post my results for both.
I'm wondering if anyone can help me figure out why there is such a difference.

My Computer
Standard Desktop: 13763

Windows 7 64bit
Intel core i5-2500k CPU@ 3.30 Ghz
Nvidia Geforce GTX 550 Ti(VRAM 4049 MB) 9.18.0013.4448
1280x720 Standard Desktop full screen

His computer
Standard desktop :2033
Windows 7 64bit
Intel Core i5-3570k CPU@3.40 Ghz
AMD Radeon HD 6450
1280x720 standard desktop full screen

I haven't been able to figure out why they are so different in score. If I could get someones help please I'd be very thankful.