About the half multiplier and the memory controller it would look like this:

GHz - DDR2-800 - DDR2-667 - DDR2-533 - DDR2-400
2.5 - DDR2-714 - DDR2-625 - DDR2-500 - DDR2-400
2.4 - DDR2-800 - DDR2-600 - DDR2-533 - DDR2-400
2.1 - DDR2-700 - DDR2-600 - DDR2-525 - DDR2-400
2.0 - DDR2-800 - DDR2-667 - DDR2-500 - DDR2-400

So worse memory bandwidth, 66% more L2 latency and K8 suddenly drops 10-15% in games.