there r few options:

a) tune the bios & reflash
b) if ATI card, use ATT (ati tray tools), but doesn't support voltage tuning on 5k series.
c) use s/w provided by manufacturer, such as MSI Afterburner (only works with specific gc by dat manufacture, however, lets say u own a Sapphire 5850 instead, u could flash the bios to MSI 5850 & use afterburner)

actually flashing ain't dat risky if u know how to recover from bad flash.
for nvidia, u could do a "blind flash" recovery (google the steps).

i suggest try ASUS or EVGA bios since they usually provide the most overclock ability gc.

http://www.techpowerup.com/vgabios/index.p...face=&memSize=0

try EVGA bios.

http://www.techpowerup.com/downloads/1762/...sh_5.91.01.html

& dis is NVflash, use to flash ur nvidia gc bios.
all u need is create a bootable pendive, put dis file in ur pendrive, & set ur mobo 1st bootable to USB. (if no usb bootable, u'll hav to create bootable cd o floppy)

steps:
1) backup ur current bios & put it in the bootable pendive (rename it to something ez to remember such as "old.rom").
2) dl ur new bios & also put it in the bootable pendrive (rename it to something ez to remember such as "new.rom").
3) boot the from the pendrive & following r the commands.



4) if flash successful, reboot & try oc ur card again. (suggest u plug out the pendrive & dun chance the 1st boot device setting yet, coz later might hav to blind flash)
5) if flash fail o not compatible (no display), dun panic, ur pc actually still boot, wat u hav 2 do is blind flash. wait manbe half a minute, assume dat it edi boot the pendrive (just dat u cant see display), & den use force flash but dis time flash bck to ur ori bios.

edit: som typos

This post has been edited by tech3910: Mar 7 2010, 03:59 PM