The PNY XLR8 D22GX85XL-5 dual channel memory kit has a default clock speed of DDR2-1066 MHz while using 5-5-5-15 timings and a voltage of 2.2V. The XLR8 D22GX85XL-5 is compatible with nVIDIA's EPP standard so that means if you're a novice overclocker, team the memory up with the proper motherboard and the system will overclock itself.