Question 2nd GPU not working -is it my Asus motherboard?

[tkdoherty]

I'm doing a new build with an ASUS ROG Maximus XI Hero wi-fi motherboard, i9 cpu, 32 gb memory, 1 TB M2.2 and 15 TB hard drive. I want to set up the system with dual graphics cards for GPU 3D rendering. I've got a Gigabyte RTX 2080 card and an EVGA RTX 2070 card. My problem is that the MB does not recognize whichever card I put in the second PCI-e x16 slot. Either card will work in the first slot, but neither is recognized in the second slot. I updated the MB bios and also the chipset drivers, but the system only shows one card. I'm doing two builds, and both motherboards (same model) have the same issue -only one GPU is recognized in the first PCI-e x16 slot, nothing in the second slot. The system has an 850 watt power supply, and I even tried powering the second card from a separate power supply in case low power was the issue. Nothing I've tried works, and I've been unable to add a second card to the system. It seems like a MB issue, but ASUS has always been reliable for me in the past, and the fact both of my XI Hero motherboards have the same problem has me scratching my head...

 

[Eximo]

You shouldn't have any issues with 8x/8x using the two slots provided by the CPU. The other slots will be through the chipset, I believe the third PCIe slot is only 4x.

Coupled with an M.2 SSD that also uses PCIe, and depending on how your other drive is hooked up, you may be starving the board of available lanes. (Wifi will use up some too)

I suggest a thorough reading of the manual to see what lane allocations exists and compare it to what you have put together. If both are doing it, has to be the way the components are being used. Might be necessary to disable or move some of the hardware around.

 

[Calvin7]

Both the GeForce RTX 2080 Ti and GeForce RTX 2080 support NVLink to chain together two or more cards, but it appears the GeForce GTX 2070 does not. A visit to each of the new card's product pages on NVIDIA's website essentially confirm this. There is an NVLink tab on the two higher end cards, but not on the more 'affordable' GeForce RTX 2070's product page. Furthermore, the NVLink description clearly leaves out the GeForce RTX 2070 while mentioning both of the pricier parts.... Read more...

 

[Eximo]

Regardless if NVLink or SLI is desired, getting the cards to show up in the system is a first step. Generally with GPU rendering it simply treats cards as a pool of processors, I do not believe the shared memory of SLI is necessary.

 

[tkdoherty]

Octane Render actually does not want the cards to be shared, so I don't need SLI or NVLink, I just need the cards to recognized. I'll take a look at the PCIe lanes. It will certainly be a disappointment if the motherboard won't support 2 PCIe cards and an M.2.