gridironcpj

Sajin
Enable it manually via regedit...
 
#1 Press windows key + r to bring up the run box.
 
#2 Type regedit and hit enter.

#3 Goto  HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/Control/Video 

#4 Identify the correct registry folders for each of graphics cards you have installed. There will be one associated folder for each card installed. To identify the correct folder for each card, you will need to review the names of each folder within the “HKEY_LOCAL_MACHINE/SYSTEM/CurrentControlSet/Control/Video” registry directory. The folder associated with a graphics card will have three or more subfolders (depending on how many PCI-E slots available on the motherboard). The values listed for each subfolder will be 0000, 0001, 0002, 0003, 0004, and Video. Review only the subfolders labeled as "0000". You will know you have selected the correct "0000" subfolder when you see a registry labeled “DriverDesc” with a value that matches the graphics card you have installed. 

#5 Right click on the folder labeled “0000”. Select “New”, then select “DWORD (32-bit) Value“, then enter “RMPcieLinkSpeed” for the name of the registry. 

#6 Right click the “RMPcieLinkSpeed” registry you just created, then select “Modify”, then enter “4” as the data value and verify that the “Hexadecimal” option is checked under “Base”, and then select “OK”. 

#7 Repeat steps 5 and 6 for each graphics card associated folder (named “0000”) 

#8 Once you have completed creating the RMPcieLinkSpeed registry for each card, close the Registry Editor window and restart your computer. 

#9 Once your system is back into operating system environment, run GPU-Z and verify that the “Graphics Bus interface” value shows PCI-E 3.0 for each card. 

Ah yes, I remember this method from Windows 8.1.  Don't you need to do this every time you update your drivers?  Also, I only came across one folder from step 4, instead of 2 (one for each card).  SLI is working for me and I remember doing this in Windows 8.1 with two different folders, one for each card.  Perhaps Windows 10 condenses them into one?

gridironcpj
I performed a clean install of the Nvidia drivers to see if that would cause the second card to appear in the registry.  This worked and now both cards have Gen 3 activated.  However, a clean install always turns SLI off, so was I supposed to have SLI off before attempting this?  If so, that may have been why I couldn't see the second card in the registry.  Thanks for the help!

jdcranke07
This actually did the opposite of what I wanted and what you said Sajin. Adding RMPcieLinkSpeed with a hexidecimal value of 4 made my GPU run in PCIex16 1.1 mode.

jdcranke07
Unfortunately, I tried the regedit in admin first. It did nothing. Then I tried the .exe you listed and it activated and then nothing happened. Currently doing a clean install again to see if that will do the trick. If that doesn't work, then I'm at a loss. Is there by chance a power savings setting or some type of BIOS setting that could allow the Xeons to keep everything in a low power state until rendering happens? GPU-Z's rendering option is still either having all GPUs at 2.0 or even scaling them down to 1.1. Still have not seen 3.0.

jdcranke07
Yeah, it's the latest that Asus released. I wish that I could get in contact with the Asus techs, but for some reason there was a disconnect during the call and now it won't let me get a call through to them. Just waiting it out a bit more to try that again.
 
Now I do have a quad port NIC installed on the fourth blue slot and a sound card on the 3rd black. GPUs are in slots 1,3,and 5 (blue), Sound card in slot 6 (black), and NIC in slot 7 (blue). As far as I can tell, there should be no shortage of PCIe lanes and that shouldn't be an issue, right?

arestavo
Who cares if it runs at X16? X8 is fine for SLI or non-SLI (1-3% difference in BENCHMARKS - not gaming), you want it to run at PCIE 3.0 instead of PCIE 2.0 right? Because PCIE 3.0 X8 has the same bandwidth as PCIE 2.0 X16.
 
The last thing that I would try would be to run CC Cleaner to clean up your registry. Run it a couple of times to make sure you cleaned out all of the garbage in the registry.
 
AND YES! RESTART your computer! We aren't quite there, software technology wise, with not needing to restart yet. Especially for registry changes.

arestavo

gridironcpj

arestavo
Who cares if it runs at X16? X8 is fine for SLI or non-SLI (1-3% difference in BENCHMARKS - not gaming), you want it to run at PCIE 3.0 instead of PCIE 2.0 right? Because PCIE 3.0 X8 has the same bandwidth as PCIE 2.0 X16.
 
The last thing that I would try would be to run CC Cleaner to clean up your registry. Run it a couple of times to make sure you cleaned out all of the garbage in the registry.
 
AND YES! RESTART your computer! We aren't quite there, software technology wise, with not needing to restart yet. Especially for registry changes.

It matters for the combination of g-sync, SLI, and X79.  Without PCI-e 3.0 enabled, I was taking a 25-30% performance hit in 3DMark and in games.  With PCI-e enabled, that performance hit decreased to 5-10% depending on the resolution.  It isn't an issue for a single GPU.  Please keep in mind I've only tested this for X79, not any other platforms.  

You might want to really read what I wrote.

At one point I had two 980 TIs in SLI on an X79 with a 3930K. It was minimal difference in FPS between PCIE 3.0 X16 and X8.

P.S. - Gsync only kicks in around 30FPS to the max refresh rate of the monitor when it is turned on. It has no bearing at higher than the refresh rate of your monitor, and it is fairly unimportant to this particular discussion.

squall-leonhart
The GEN3 tool doesn't work  via powershell, this might be where some people are seeing it fail as powershell is now the default item in the winkey+x menu.