Hi all, Recently upgraded my memory from 1GB ddr2 (533MHz 2x512mb) TO 4GB 6400 Crucial Ballistic and initally had problems could only use 3GB wouldnt boot with the 4GB read some forums and had to reduce 800mhz to 667mhz. Now it recognised the 4GB but still was crashing so having spoken to crucial they advised upping the memory voltage. so it was at 1.8v (AUTO) increased to 2.085v. Seemed to working fine trouble is ever since my messing in BIOS the hard drive light is on constanly and making in use noises. Should i be concerned? Have turned off search indexing, disabled bit torrent, done a memory test was good done scandisk no problems found. I think the voltage may have changed something?? everything else is on auto.vcore, nb core, vcore offset. Anyone know whats wrong? Also i downloaded the lastest motherboard drivers from nvidia 15.08 and when its installed my Hitachi hard drive comes up in safely remove hardware! So i changed it back to the previous version 15.00 I have Asus P5N-E Sli nforce 650i mobo, Core 2 Duo E6400 Vista home premium 32 Bit Would appreciate any help thanks!