Is your current PC using core i7?
If not then cannot, cos the core i7 uses a socket called 1366
So it means that if you are using the old socket 478 pentium 4 or
even the newest socket 775 Core 2 quad, the Core i7 will
not fit into the socket.
The core i7 mainboard is the x58, and it uses onli ddr3 rams.
Cheapest bundle for I7 940with a good mainboard will cost around
thousand dollar for now.
2gb ddr3 ram cost $83 if i remember correctly
Moreover, the x58 does not comes with onboard graphics, that means
you have to buy a pci express 2.0 graphics card if your old card is
an AGP