• Some users have recently had their accounts hijacked. It seems that the now defunct EVGA forums might have compromised your password there and seems many are using the same PW here. We would suggest you UPDATE YOUR PASSWORD and TURN ON 2FA for your account here to further secure it. None of the compromised accounts had 2FA turned on.
    Once you have enabled 2FA, your account will be updated soon to show a badge, letting other members know that you use 2FA to protect your account. This should be beneficial for everyone that uses FSFT.

862MHz GPU Clock Limit Fix for hd3870

E

eric66

Gawd
Joined
Sep 16, 2007
Messages
920
As some of you may have noticed there is a strange limit in GPU frequency on RV670 based card.
The maximum stable frequency seems to be around... exactly at 862MHz...

I have seen some wild speculation about a driver problem or a GPU limitation.
All wrong.

Lets put it this way:

'There is a mean bouncer standing outside of your favorite bar (863MHz).
Bouncer´s name: is PLL VCO Divider

The frequency of GPU internal PLLs are changing with GPU frequency.
At certain points the PLL must change it´s divider to maintain the frequency at correct range.
If the divider is not changing for some reason the frequency of the PLL will raise too high and it will flip.
This is what happening at 862MHz.

It is pretty much the same thing on cars.
To reach higher speeds you need to put in a bigger gear.

The problem can be easily fixed by updating the new bios.
Unfortunately I don´t have a bios for HD 3850 cards, but it should also be available soon.'

http://www.armada.fi/HD3870/HD3870_PLLVCO_v010.071.zip

taken from xs forums post some oc results 3870 owners :D
 
You must log in or register to reply here.
Back
Top