thank you for replying, I am glad that i found a modded nv driver which made me can install k5100m driver successfully, i forgot to do it without signature before so it failed. Anyway i can use K5100M driver now without using modded vbios , but i got another problem, my laptop seems only can run 1333mhz when i put 3*1600 ddr3 DRAM into my laptop ( i tried only put 2 DRAM in it and it works normally, with 1600mhz speed.) so I would like to have a modded bios to let me use full speed of DRAM, like xmp profile function etc.. i have put the bios which im using now, it was downloaded from MSI official website for GT 60 2PC, however after i flashed the bios, seems detected me as GT60-2OC/OD now, i couldn't even use the steelseries engine driver for macro now. hope u can help me :x