SuperTalent PC2-6400 2GB Dual Channel Kit
 

SuperTalent does a nice job of exceeding my expectations, getting all of the way to 880MHz, while maintaining 4-3-4-8 timings. I did have to juice them to 1.9V but lets be serious here, I put my OCZ modules at 2.0+V frequently (I must note however that the OCZ heat spreaders are much more substantial then those SuperTalent uses, of course there is yet to be proof of any value to overclocking performance, I digress however).