gtx 680 The Grand SLI Adventure!

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Welcome!

 

We are going to conduct an experiment! I have always wondered. Can you SLI a GTX770 2GB with a GTX680 2GB? Will the GTX 680 need to be flashed to a 770? These questions will be definitively answered.

I searched over like 10 google pages (thats like half the internet) and I did not see anyone that ACTUALLY tried SLIing these cards together. Both of the sides have provided theories as to why or why it will not work but no one has tried it. I have an EVGA Superclocked GTX 680 2GB card that I got back in 2012. It's stable and is a daily reliable workhorse. I considered SLIing this because I could get the card cheap and I knew the GTX770 is in fact a refresh of the 680. Some other chatter I saw about this.
http://www.tomshardware.com/answers/id-2182003/sli-gtx-680-gtx-770.html
http://www.overclock.net/t/1396119/can-a-gtx-680-sli-with-gtx-770

But no one confirmed a result. I have seen confirmation that a GTX 680 can be bios flashed to  GTX 770 with gpu boost 2.0 functional and I know my card can run the 770 bios speeds.
This gap in humanity's knowledge ends tomorrow (probably) as I flash my GPU to a 770 and SLI to some random GTX 770 I pick up off Kijiji (Canadian Craigslist) and hope it JUST WERKS. : ^)

I am acquiring the 770 tomorrow (later today technically) and will report further.

I'm going to thank this thread in advance as I'm sure I'm going to be using it.

UPDATE 1: Having some trouble with the flashing process. I'm using a GTX770 2GB Superclocked bios as I have a 680 2GB Superclocked, but no matter which switches I add to the nvflash command it refuses to flash, citing GPU mismatch even if I use "nvflash64 -4 -5 -6 770.rom", I tried using --protectoff and it seemed to turn off the write protection. " -f " isnt forcing it either. Any advice?

 

EDIT: After downloading old version of NVFlash it's ALIVE!

 

Update 2:

As seen here we now have access to temp limit (GPU Boost 2.0). The card seems stable under 100% real game load. temps and speeds are the same but the bios shows up as 770 when i check using "nvflash --version"

At this point I have a gtx 680 flashed to a 770 and another gtx 770. I just need to get the pci-e power cables and an SLI bridge that is spaced properly. THEN THE FUN REALLY BEGINS.

 

Update 3:

 

So the cables came and I have installed both GPU's and both are recognized by the nvidia driver, unfortunately, it appears the driver is also smart enough to refuse to SLI them, never fear however. There is software such as hypersli that may make this work.

 

Conclusion:
Well, the experiment has been fun. I hope people in the future that have the same question I did see this thread.

As it turns out, GTX 680 SLI'd with GTX 770 is not possible even with a flashed card. However, we can see that using differentsli auto, you can in fact make it work, you do not even need to flash the card to a 770. I could undo mine but it's stable and I'm lazy now

 

 

I've checked in a couple games and I'm getting good scaling, about 80-95%. It appears to be working well. I could not have finished the process of using different auto sli as quickly as I did, without the super helpful thread on techpowerup, and this post in specific that details exactly which driver is supported and how to enable this functionality.

https://www.techpowerup.com/forums/threads/sli-with-different-cards.158907/page-89#post-3673305

 

The main downsides to this are that it's basically only compatible with somewhat older drivers (currently using a driver from may), and that you must enable test mode in windows which gives your desktop an annoying little message.

 

Overall I would only recommend this if you are like me and find a cheap but technically incompatible card and want to eek out a few more months from your system.

 

TL;DR: No you can't SLI a 680 and a 770 unless you use DifferentSLI Auto, even a flashed card will not work.

[r4tch3t]

Oh interesting

[MVPernula]

Now THIS is the content I signed up for!

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The 770 I bought does in fact work fine! I am now struggling with the fact that I misplaced my additional pcie cables for my power supply so I can't run SLI until then. In the meantime I'm going to start working on getting my 680 flashed to a 770.

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UPDATE 1 in Main Post

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UPDATE 2 In Main Post

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UPDATE 3, ITS HAPPENING

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CONCLUSION IN MAIN POST