NVidia SLI on z690/790 Motherboards

[MaddMutt]

Does anyone have confirmed SLI working with lower end Video Cards? I have checked the spec’s for the z690 and only MSI and EVGA list Nvidia SLI Technology support. I have a ASUS z590 Apex with a 11900k that refused to run my 2 GTX-450’s. I checked the manual and it stated “NVidia SLI Technology supported - Support Varies with Different Cards. I have tried my GTX-450/550/560 and it posts with a single card. When I insert 2 cards, the board refused to post. I have checked both Primary/Secondary PCIe slots and they work when only 1 card is used. I first thought it was the 11900k (Because of PCIe Gen 4 support) so I purchased a 10900k (still no luck) and then a z490 Hero which worked.

I’m also looking to run 2 GTX-780Ti/980Ti  Classifieds/Kingpins BUT the z490 Hero does not have an extra GPU power connector on the motherboard. Is this needed if I not running Dice/LN2??

Thank You For Your Time

In Reading and Replying? 

[TerraRaptor]

For my z690 formula it seems to be broken lerain jys13008 that don't properly split pcie into x8/x8. So maybe you have the same issue with buggy multiplexors

[MaddMutt]

^ Thank You for this advice ?  I went into the BIOS and set the PCIe split as 8+8+NVME and got an DXE error 63. I then installed a GTX-590 in the first slot and again received a DXE error 63. The MB will run a single gpu card as x16 but can not handle having to split the lanes ? I already have the MB setup for cold so there is no RMA option. 

This is an Update on my problem with the z590 Apex. I also asked over on HwBot this same Question and was told it might be my MultiPlexers are Buggy. IE not wanting to split my PCIe lanes

I went into the BIOS and set the PCIe lanes to 8+8+nvme and got a Error Code 63 which is a DXE error. I also installed a GTX-590 and got the same error code 63. The MB will run a single gpu card as x16 but will not handle having to split the that same lane for a multi card setup.