For being scrounged together from old parts this build definitely ended up being a lot pricier than I anticipated and I could definitely have gotten better performance for less money, but meh, the heart wants what it wants.  Right now I'm just running some tests and messing with sliders in Precision X1, so I'd love to hear any tips other people might have and what results you've gotten.  For the CPU though, I do find that if I run the OCRobot and also enabled XMP then I will get post code 55, though either by itself is fine, and I'm just doing a Memtest run right now to make sure the memory isn't the problem and I suppose that letting bots overclock for you kind of defeats the purpose of enthusiast spec hardware.

KP cards. 👍😎

list your hardware
  MB & BIOS version
  CPU
  PSU
  OS
 
 
 
Dual 1080Ti KP
 
3 way & 4 way sli - in current PX1 ? - not sure as when I had 3-way SLI - the new version of PX1 did not exist
 
 
My Rig Nibbler EVGA X99 Classified EVGA 3080Ti FTW3 Ultra 1600P2 (previously 3-way Titan X)

Cool Rig
 
I just bought a EVGA X299 Dark, i7-9800x & 32 GB of Corsair  3600mhz Vengeance RGB Pro SL Ram ---> its my next project
 
How well does the Optane drive work on the X299 Dark? 
 
Are you using a Optain memory only M.2?
 
I was under the impression after looking at Intel sit that X299 chipset just treated it like an ordinary SSD ..... no acceleration, for the OPtane with SSD drives

Cool GTX
Cool Rig
 
I just bought a EVGA X299 Dark, i7-9800x & 32 GB of Corsair  3600mhz Vengeance RGB Pro SL Ram ---> its my next project
 
How well does the Optane drive work on the X299 Dark? 
 
I was under the impression after looking at Intel sit that X299 chipset just treated it like an ordinary SSD ..... no acceleration

Yeah the Optane just gets treated as any other SSD, I think the acceleration only really helps if you're pairing with a hard drive, not much noticeable benefit with another NVME.  I just got it because I figure I'd populate that second M.2 slot with something, and Optane is supposed to have good random read/write performance so I figured it'd be a good choice just to install Windows on, plus they're on sale at Newegg now.
 

Cool GTX
thanks for the Optane information
 
your case with those 2 GPU making heat, might have to keep the side off of your case

I'm not clear on the specifics, but as far as I can tell the Optane acceleration is just basically using the drive as a cache for a slow HDD or SATA drive, so I figure it's better just to use it as a boot drive and retain the option to install whatever else you want on there.
 
And yeah, I'm getting all my tests out of the way while I still have it set up as an open bench.  I figure I will eventually put this thing on water, but I don't know if it's really worth losing all the flexibility once your loop is installed, nevermind the effort and cost of tracking down discontinued parts for old hardware.  Did they ever even sell the 1080 Ti Hydro Copper as a separate item, or was it only ever packaged with the card?

 
Well I finally got around to putting this thing in a case and also managed to score a third 1080 Ti KPE, but my moment of triumph was quickly dashed because while this system ran fine with the 2-way SLI setup, I've had nothing but problems getting the 3-way SLI working.  I was unable to even get through installing the display driver before it gave me the nvlddmkm.sys error, and I thought it might be an issue with the new GPU being faulty or the SLI bridge being insufficient, as it is just the one that came with the motherboard and not the fancy Pro HB one.  However, while any GPU by itself is fine, any attempt to have multiple GPUs installed, even without the SLI bridge, gives me the same problems.  I tried reverting back to the setup I had working before using the two GPUs I had originally and reverting back to the older driver version (528.49), but then I saw that Windows was not detecting the second GPU or allowing me to enable SLI, even though it was showing up in HWinfo and the indicator light on the PCIe slot showed that it was populated.  
 
I'm not panicking, yet, but I also got reminded of the folly of trying to run 3-way SLI (and eventually I'd like to do 4-way) these days  I figured that everything would be a tight fit but I wasn't anticipating there to be literally no space whatsoever, and the heat will assuredly be wretched regardless of how many fans I stick in there.  I suppose I can always put the whole system on water later on, but I should get the thing working first.  If anybody has ideas, I'd love to hear them.

vcbb10
My first thought is maybe a power issue?  I think from your picture you have the supplemental 6 pin power plugged into the board.  I don't have that specific motherboard, but, is there an option in the BIOS to enable the supplemental power (my older board has a BIOS option to enable this)?
 
I assume you used DDU prior to installing/updating drivers?

Hmm I’ll check but I just assumed the supplemental 6 pin is enabled whenever it’s plugged in, didn’t see an option in the BIOS for it. And yeah I did use DDU but I didn’t always make sure I was in safe mode. I read in another thread that it might be an issue with Windows registering the GPUs under different driver versions, but I need to play around with it some more. Thinking it is not a hardware issue though unseating the GPUs requires poking at the release clip with a letter opener which I’m not super comfortable with. I should just use those dip switches to disable the PCIe slots instead of physically removing the cards.
 
UPDATE: The plot thickens, after trying every conceivable combination of re-seating cards and toggling PCIe dipswitches, I found that one of my GPUs is faulty though strangely enough it wasn't the new one but one of the two I had in there before that had been working fine in the test bench setup.  I can't think of anything I could have done that would have damaged the card or anything like that, so maybe I can still salvage it.  At least I'm back to a functioning two-way setup though.  Also, speaking of thicc, I'm a bit concerned about the structural integrity of the system even if I manage to get everything working again, since there is no space between the GPUs to install the support brace that came with the case, and they are just leaning on each other which can't be good in the long run.
 

 
This is what I'm getting on the faulty GPU after a failed driver install.  The odd thing is that I'm getting a whole range of different results - sometimes it doesn't POST at all, sometimes it crashes when I try to install the driver and I get something like this, sometimes it successfully installs the driver but then crashes while running Heaven.

Also, I have been looking at this thread:
 
https://forums.evga.com/3-way-SLI-GTX-1080-Ti-how-to-do-it-m2748218.aspx
 
Is it true that you need a pro SLI bridge to get 3-way working and that the regular one that came with the MB won't work?  I have been looking to find the appropriate one, model no. 100-3W-0032-LR, but can't find it anywhere.  I did manage to track down a 4-way bridge, but the connector layout on that doesn't seem to work for 3-way.  Gonna head back to the office later and give it another go, fingers crossed that I didn't end up bricking a perfectly good GPU carelessly tinkering about with insufficient hardware, bah.
 
Update: More crashes and artifacting, the GPU seems to be dead.  I can only assume that it was on the verge of failure and my tests just pushed it over the edge, a real shame honestly because these KPE cards are pretty hard to come by.  

vcbb10
Yeah, it's a shame when a KPE dies.  If you have narrowed it down to 1 card, you might consider trying to get it repaired/fixed.  Even out of warranty, finding a repair shop to keep KPE cards going just seems right.
 
I recently sent my 980 KPE to a repair shop.  We exhausted everything (core swap, vram, vbios chip swap/flash...), unfortunately, it can't be repaired.  I even sacrificed a working EVGA 980 as a parts card to try to keep it going.  If you can, get it repaired, IMO, the 1080 Ti KPE is the most beautiful card made.

 
I thought about doing that, but I figured that in all likelihood it'd go down like in your experience where a lot of work goes into ultimately not being able to salvage the card.  And not gonna lie, probably the main reason I decided to go with 1080 Ti KPEs was because of aesthetics.  I could probably have gotten better performance for less money from Titan Xps, especially since those blower fans will do better in 3 and 4-way SLI with the cards all jammed together like that.  I understand the rationale for why Kingpin went with those hybrid coolers for later GPUs, but I'm not a fan of AIOs in general and going Hydro Copper means going down the whole custom water cooling rabbit hole which I don't want to do at the moment.  If they had just something that basically looked like a 2080 Ti FTW3 with a fat copper heat sink I would've been there all day for it.

Just my damn luck, got another Kingpin card in yesterday and that one was dead too.  Any type of 3D load just crashes the system, even with the power limit dialed down it can't even handle the GPU-Z render test:
 
https://www.youtube.com/watch?v=_oyEAI78fp0
 
I do want to try and salvage these GPUs if possible, but I'm not able to even find any repair shops that will do this and I'm not sure whether this is an issue that can be fixed or if the card is just totally bricked.  At this point, I think it might be a good idea if I stopped chasing the 3 and 4-way SLI waterfall and just, I dunno, used my computer to do stuff or whatever.  

vcbb10
The guy on "Northwest Repair" treated me fairly when working on my 980 KP.  It wasn't repairable, but, he put a lot of work in on it and returned it at no charge (no repair, no charge).  Rates also seemed reasonable to me.
 
Contact info:
You can look him up on YouTube: https://www.youtube.com/@northwestrepair
For repair, please contact me on discord https://discord.gg/VnGFRqzrGu
Or email me at tony@northwestrepair.com (ignore automatic reply)

Awesome, I reached out to him, let's see how it goes.

Hoggle

rjohnson11
Good to see that EVGA GTX 1080ti (two of them) still has some life left. 

The 1080 is still a pretty good card if someone is only planning on gaming at 1440p or maybe in this case using SLI for 4K. It also of course depends on the games he is interested in playing since a lot of great games came out when the 1080 was the top of the line graphics card.

SLI is making a comeback, it’s like Dennis from 30 Rock said, technology is cyclical. Only a matter of time before quad 5090s is what peak performance looks like.

PwrdOff

Hoggle

rjohnson11
Good to see that EVGA GTX 1080ti (two of them) still has some life left. 

The 1080 is still a pretty good card if someone is only planning on gaming at 1440p or maybe in this case using SLI for 4K. It also of course depends on the games he is interested in playing since a lot of great games came out when the 1080 was the top of the line graphics card.

SLI is making a comeback, it’s like Dennis from 30 Rock said, technology is cyclical. Only a matter of time before quad 5090s is what peak performance looks like.

Honestly I wouldn't be shocked if multiple GPU doesn't make a comeback as it could be that someone like Intel will let partners have more freedom with doing things like SLI. It would be great to get back to some of the crazy extreme boards we saw in the early days of graphics cards. 

I think nvidia is done with SLI.  IMO