difference in ddr2 667 and 800 ram

[faith4]

is there like a difference in performance in ddr2 667 and 800 ram ?
does it increase performance by abit or alot ?
iam thinking of getting "Corsair XMS2 TWIN2X2048-5400C4 2GB 2X1GB PC5400 DDR2-667 CL 4-4-4-12 240PIN Dual Channel Memory"

over this "Corsair XMS2 TWIN2X2048-6400 2GB 2X1GB PC6400 DDR2-800 CL 5-5-5-12 240PIN DIMM Dual Channel Memory"

 

[mammikoura]

yes there is a pretty big performance difference. The ddr800 is maybe like 15% faster.

 

[lhuser]

It's going to feel a difference, but not like 2x faster. Around what mammikoura said; 15%.

It would be best to have faster chips to avoid bottlenecking.