[Guide] Definitive Maxwell II (2) vBIOS Modding
How To: vBIOS mod your Maxwell 2 based GPU
Introduction
Welcome my minions to another guide bought to you by yours truly, today I will be showing you how to tweak the snot out of your Maxwell II based GPU. They may be a little older now, but they still have better IPC than Pascal, meaning they don't need to clock as high to match or beat equivalent Pascal based GPUs. Make no mistake, Maxwell II is still a beast, particularly if you have a GTX 980 or 980Ti.
Tools of the Trade
You will need the following;
Maxwell II BIOS Tweaker
Copy of your vBIOS (from both primary and backup EEPROM)
Joedirts modified version of nvflash
Notes: To make a copy of your vBIOS you can either use GPU-Z, some manufacturer provided software offers the facility to backup your vBIOS such as Gigabytes VGA @BIOS utility, or you can use the following nvflash command; nvflash.exe --save backup.rom.
Now, unlike a lot of vBIOS modding guides that often use a lot of text burying the important highlights to know among it I'm going to use screenshots with bullet point explanations.
Most of this is self explanatory.
http://i.imgur.com/FM1jMDz.png
TDP & 3D base entry: Standard "fallback" frequency for when the card runs out of TDP headroom
Boost entry: Maximum stable GPU speed.
Temp & Max temp target: You don't really have to change these but if you want to do some temperature fine tuning here is where to do it. The only time this may be needed is if you have replaced the cooling the card came with or the reference / manufacturers cooler has awful fans that get loud.
Boost Limit: Some vBIOSes don't have this, the ones that do you need to set it to your maximum stable GPU clock. Also be certain to pay a quick visit to the "Boost Table" tab and set the same boost limit there.
Memory Clock: Memory speed. Whatever your max stable speed is put it here. Eg; if the OC software you use displayed 8000 you would input 4000 (4000x2 = 8000).
Fan Control: Useful for if you have a loud cooling solution, RPM = fan speed in rotations per minute, TMP = temp threshold limit before fan speed increases, PER = same as RPM, only in percentage value.
The least fun tab to do modifications by far on more recent nvidia cards, for the first 4 entries set the minimum value to the voltage your max stable OC requires and the max voltage to whatever headroom you would like to have.
http://i.imgur.com/mbmnS91.png
Notes: I don't recommend setting a voltage upper limit of more than 1.28v unless you are using extreme cooling. Also remember that some cards are sensitive to OCP, so as a generic rule I'd say a recommended universal maximum voltage is 1.24v.
http://i.imgur.com/8gVyITO.png
http://i.imgur.com/2lc3ZSJ.png
TDP Limit: Maximum power draw for your card. Remember that the mainboard PCI-E slot can provide 75w, 6-pin PCI-E connectors can provide up to a additional 75w per connector, and 8-pin PCI-E connectors can provide up to a additional 150w per connector. So for example if you have a GTX 980 with a 6-pin and 8-pin connector it would be 75w (slot) + 75w (6-pin) + 150w (8-pin) for a maximum of 300w.
Notes: Bare in mind that just because the card you have has connectors for higher power draw than what may be set as vBIOS defaults it does not mean the physical components on the card will be able to handle it, as such increase these values with extreme care!
PCI-E slot power draw: Do NOT under ANY circumstances raise the default and max values beyond 75000 (75w) you could end up blowing the slot on your mainboard!
PCI-E rail 1 & 2: The maximum for these should be based on if you have 6 or 8 pin connectors. As you can see here for some reason the maximum is 159000 (159w) which is actually over the limit of what even a 8-pin PCI-E connector can provide which is rather puzzling. It may or may not effect stability and \ or overclock ability I would suspect it would depend on how good your PSU is.
Power Limit: Set maximum to the same value as TDP limits and max power limit to whatever your board is capable of, eg; if you have a board capable of 375w (PCI-E slot x 2 8 pin connections) set TDP limits to 350000 (350w) then set Power Limit max value to 375w. This means the board will draw up to 350w before any throttling will kick in, the 375w value is for the power target limit in OC software, allowing the card to draw up to 375w.
That's all the changes you should need to make, now just save the changes you made and flash the modified vBIOS to your card.
Downloads
Joedirt NVflash & Maxwell II BIOS Tweaker v1.36
