Intel i7 CPU Compatibility with my system

Hi there,

I was looking to upgrade my PC again and I think it's now time to spend some $ into a new CPU. Here's my current system configuration:

OS Microsoft Windows 7 Ultimate
Version 6.1.7601 Service Pack 1 Build 7601
Processor Intel(R) Core(TM) i3 CPU 540 @ 3.07GHz, 3725 Mhz, 2 Core(s), 2 Logical Processor(s)
Motherboard ASRock H55M-GE
Display NVIDIA GeForce GTX 560
BIOS Version/Date American Megatrends Inc. P1.30, 10-08-10
Installed Physical Memory (RAM) 8,00 GB
Total Physical Memory 7,99 GB
Available Physical Memory 4,74 GB
Total Virtual Memory 16,0 GB
Available Virtual Memory 12,2 GB

I want an Intel i7 but I don't have 500 bucks to spend on it so I was looking through the used ones on eBay. I have a budget around 150-200$ max. I found these which seems interesting but I have no idea if they would fit in my current system configuration and/or if I need the fan and heatsink since I already got those with my i3 CPU:

http://www.ebay.ca/itm/Intel-Quad-Core-I7-870-2-93Ghz-8...

http://www.ebay.ca/itm/Intel-Core-i7-I7-960-3-2-GHz-Qua...

Can anyone tell me if this is a good idea or suggest something else?

Thanks in advance!