First computer build - looking for some help

[sk82jack]

Can I ask what is the difference between MSI GD55 and GD65 if I only plan to OC to 4.4 to 4.6 Ghz on a i5 2500k?

Here is a good comparison chart of all the physical differences. Doesn't look like much difference apart from the 2 extra eSATA ports and 2 extra SATA III ports, a higher grade vrm and dual BIOS.
But the difference in price is hardly anything.