Nice. I've got some Geil memory myself. It's been running stable overclocked for ages now.

I forgot to mention that they should probably be installed into the same colour sockets too, to make them run in Dual Channel mode.

Normally if you have 4 sockets, 1 and 3 will be say blue, and 2 and 4 will be black, for example.
Put them in either 1 and 3, or 2 and 4