Need help with 970 SLI

[Dunkan77]

Hello guys,

I've got an MSI gaming 970 and an EVGA SC 970 with the acx 2 cooler on it and they don't want to SLI. I was wondering whether that was because I need to use both SLI fingers on the cards but that's hard to do since the MSI card has a cooler that's taller than the PCB itself. Is it because of that that I can't SLI them? I figured it isn't required since motherboard manufacturers provide a "single width" bridge for 2-way and doubles for 3 and 4 way.

 

I also checked the memory manufacturer since that was another thing to watch out for and the MSI card has Hynix VRAM whereas the EVGA cars has Samsung chips. I also tried both orientations for the SLI bridge and neither work. I checked of they're both detected and they are.

 

Does anyone have any idea why it's not working? Thanks for any additional info

[Bananasplit_00]

im pretty sure you need identical PCB cards to use SLI

[Leonius]

2 minutes ago, Bananasplit_00 said:

im pretty sure you need identical PCB cards to use SLI

not necessarily, power implementation and clock speeds are not really relevant. But these newer generation cards have become more difficult to combine.

10 minutes ago, Dunkan77 said:

Hello guys,

I've got an MSI gaming 970 and an EVGA SC 970 with the acx 2 cooler on it and they don't want to SLI. I was wondering whether that was because I need to use both SLI fingers on the cards but that's hard to do since the MSI card has a cooler that's taller than the PCB itself. Is it because of that that I can't SLI them? I figured it isn't required since motherboard manufacturers provide a "single width" bridge for 2-way and doubles for 3 and 4 way.

 

I also checked the memory manufacturer since that was another thing to watch out for and the MSI card has Hynix VRAM whereas the EVGA cars has Samsung chips. I also tried both orientations for the SLI bridge and neither work. I checked of they're both detected and they are.

 

Does anyone have any idea why it's not working? Thanks for any additional info

Yes it is probably the memory controller, and if it is there is pretty much nothing you can do. However did you test weather both cards actaully work on their own? and you could try swapping their positions, just to see what happenes.

[stealth80]

24 minutes ago, Bananasplit_00 said:

im pretty sure you need identical PCB cards to use SLI

I did it with non identical EVGA 970's, however I remember on the EVGA website that not all their 970's could be SLI'd together, some cards just wouldn't play

[Bananasplit_00]

8 minutes ago, stealth80 said:

I did it with non identical EVGA 970's, however I remember on the EVGA website that not all their 970's could be SLI'd together, some cards just wouldn't play

well i have never gotten it to work, at all. identical PCB 660s and nope. two ASUS boards were all i had to try on and they are probably to blame tbh lol

[stealth80]

2 minutes ago, Bananasplit_00 said:

well i have never gotten it to work, at all. identical PCB 660s and nope. two ASUS boards were all i had to try on and they are probably to blame tbh lol

https://www.evga.com/support/faq/afmviewfaq.aspx?faqid=59534

[Bananasplit_00]

10 minutes ago, stealth80 said:

https://www.evga.com/support/faq/afmviewfaq.aspx?faqid=59534

refrence boards m80, and 660s, not 970s. i would never SLI 970s because of all the problems i have heard about it, same with 980s

[stealth80]

16 minutes ago, Bananasplit_00 said:

refrence boards m80, and 660s, not 970s. i would never SLI 970s because of all the problems i have heard about it, same with 980s

well I didn't have any problems, that's my point, they were a great combo as well

[Dunkan77]

11 hours ago, Leonius said:

However did you test weather both cards actaully work on their own? and you could try swapping their positions, just to see what happenes.

Both cards do work on their own yes, and Yes I have tried swapping the cards' positions and the load just gets transferred to whichever card is on top as it should.

11 hours ago, stealth80 said:

I did it with non identical EVGA 970's, however I remember on the EVGA website that not all their 970's could be SLI'd together, some cards just wouldn't play

Well I'm not even staying within EVGA's lineup..  
 

 

12 hours ago, Leonius said:

Yes it is probably the memory controller, and if it is there is pretty much nothing you can do

Ugh.. I would've hoped it was because I need to use bot SLI fingers but that's okay I'll manage. It's not like I'm missing on much bcoz my pook 6600K is already pegged at 100% in BF1 1080p. I need to upgrade that one day sadly

[Phoenix Fieryn]

13 hours ago, Dunkan77 said:

MSI card has Hynix VRAM whereas the EVGA cars has Samsung

I think my 2 EVGA 970 FTWs had hynix and samsung memory controllers and they SLI'ed fine. Then I sold them

 

50 minutes ago, Dunkan77 said:

It's not like I'm missing on much bcoz my pook 6600K is already pegged at 100% in BF1 1080p.

I'm also wondering why BF1 is maxing your 6600k too, I don't think my 4790k was maxed in BF1.

[Dunkan77]

2 minutes ago, Phoenix Fieryn said:

I'm also wondering why BF1 is maxing your 6600k too, I don't think my 4790k was maxed in BF1.

Mine doesn't have hyperthreading  I guess BF1 really leverages CPU power and speed nicely and I didn't know that when I purchased the i5 sadly.. If anyone has a cheap-ish 6700K to sell I'll grab it off ebay or something. Because a single 970 doesn't even run at full load in some conquest maps like St-Quentin due to the open-ness of it and all the stuff to draw. I get 40 fps at times on absolute max settings 

[Phoenix Fieryn]

Just now, Dunkan77 said:

Mine doesn't have hyperthreading  I guess BF1 really leverages CPU power and speed nicely and I didn't know that when I purchased the i5 sadly.. If anyone has a cheap-ish 6700K to sell I'll grab it off ebay or something. Because a single 970 doesn't even run at full load in some conquest maps like St-Quentin due to the open-ness of it and all the stuff to draw. I get 40 fps at times on absolute max settings 

Damn that's interesting. I save and go for a bigger upgrade rather than going for the 6700k, but it's a valid upgrade path. I did not know an i5 could bottleneck a GTX 970... Hmmm... strange

[Dunkan77]

Me neither! It may also be due to my settings being absolute max so the CPU works a little harder than some other people will have it but yeah.. unexpected that even OC'ing it only gives me marginal increases in performance

[stealth80]

3 hours ago, Dunkan77 said:

Well I'm not even staying within EVGA's lineup..

 

I know you aren't, I was responding to a post saying you can't use different PCB's - You can and I did. I'm not actually sure why though, I thought it was related to GPU chip only

 

Something that maybe worth look at - I flashed the bios on both my cards. If I put the wrong bios on the wrong card the cards would still work on their own, but SLI broke - might be worth investigating some other bios's or modding your own

 

http://www.overclock.net/t/1573308/nvidia-gtx-900-cards-custom-bios-upon-request

[Dunkan77]

23 hours ago, stealth80 said:

Something that maybe worth look at - I flashed the bios on both my cards. If I put the wrong bios on the wrong card the cards would still work on their own, but SLI broke - might be worth investigating some other bios's or modding your own

Well.. I did BIOS mod the EVGA one now that you say it. I was hoping to get more voltage since it overclocks pretty poorly (1440 or so before mod) but I only got +12mV and it now hits 1470. I simply took the vanilla BIOS and had people who know this stuff tweak some of the voltages and power tables for me. Is it possible that this mod broke SLI for the card?

[stealth80]

5 hours ago, Dunkan77 said:

Well.. I did BIOS mod the EVGA one now that you say it. I was hoping to get more voltage since it overclocks pretty poorly (1440 or so before mod) but I only got +12mV and it now hits 1470. I simply took the vanilla BIOS and had people who know this stuff tweak some of the voltages and power tables for me. Is it possible that this mod broke SLI for the card?

maybe, id try a revert and see what happens