Folding Forum

The Buzzword is SLI https://en.wikipedia.org/wiki/Scalable_Link_Interface it allows multiple cards to work on video faster than any one card can process video. It does this by having seperate cards work on alternate frames of video or different areas of the screen.

F@H does not do video work, so it does not do SLI. Multiple cards will each get one WU to work on so no data will have to be shared between cards and slow them down.

So leave the cards separate and they will not suffer a hypothetical bottleneck trying to share a single WU, which F@H does not allow.

FAH doesn't care. FAH treats each gpu independently whether they are strapped together or not.

The primary function of the special cable is to coordinate the video output so that your game can display images from alternating GPUs, effectively doubling the frame rate.

Oops. Jimbo beat me to it.

Ideally,we explain it differently, so one explanation is easier for the OP to understand. I am willing to be the difficult one!

Adam A. Wanderer wrote:So, strapped for SLI or not, the Points Per Day remain the same?

Yes, F@H will see them as separate cards with separate WUs, strapped or not.

If you do video work (games) SLI will improve that.

I can make a new post, but since this is about 2 1070's I'll try here first. Sold an EVGA 1070 FTW and replaced with 2 1070 SC's. The FTW took 2 8 pin power connections while the SC's 1 each. Rebooting the system and only 1 gpu is recognized and system info shows GPU 0 & 1 Unsupported NV3 (PCI) and GPU 2 & 3 NV 1070. I tried uninstalling FAH but saving data and saw no change. Would uninstalling everything work? My main system is running 2 980ti's with no issue ...ideas?

The versions of F@H I have used do MUCH better at detecting hardware at install time than at run time, so I vote for a new install.

Thanks Jimbo, will do ..

... also, depending on how NV sees the state of affairs, you may or may not need to reinstall their drivers.

I meant to ask about the drivers also, still using 372 with my 980ti's, but downloaded the newest 385 with the 1070's..I was assuming the issues had been fixed by now?

While an old card can use an old driver, to get the most from a new card, you need a new driver that knows about that card.

Thanks for the input guys; got both working after a complete uninstall. While both cards are working I see under system info both 0 & 1 are still showing unsupported and there is no 2 & 3 this time? Not to worried since they're working, just curious.

Do you mean an uninstall/reinstall of drivers or FAH or both?

Post the first section of your log per the instructions in the signature block of my first post on this page.

Based on quite a bit of testing by a lot of folks, 372.90 seems to be the best driver for any GTX 10xx series card EXCEPT the 1080ti (which isn't supported at all by that old of a driver version) and probably the Titan Xp (same reason).
Newer drivers often introduce ISSUES that reduce performance, so it's usually best to NOT go with the "latest and greatest" on a pure folding rig.

When you change hardware FAH often gets confused if you don't at least delete the slots then add them back in as "new" slots - it's detection stuff is BROKEN and has been for a long time.
Don't get me started on how many of my rigs have slots claiming a card is a 1070 when it's actually a 1080, or vice versa.

(No, I can't optimally do all cards the same - I have power constraints that make me target a specific power consumption level on each rig, which works out to be right around 520 watts of total card TDP).

GPUs like Gtx 1070 can be strapped together using SLI but folding@home does not use it so no difference.

Strapping cards via SLI (or Crossfire on the AMD side) often causes performance DROPS when trying to use the cards in a compute environment.
It is strongly recommended to NOT enable SLI (or Crossfire) on a Folding machine.