ft1000923 wrote on 2026-07-15, 15:21:

https://m.hexus.net/tech/reviews/graphics/127 … ics-benchmarks/
https://rog.asus.com/articles/gaming-graphics … gt-dual2dt512m/

These links are incorrect, can you fix them? I suspect the 2nd should be https://rog.asus.com/articles/gaming-graphics … gt-dual2dt512m/

Have you tried it in a system and if so found a working driver?

I found https://www.techpowerup.com/gpu-specs/asus-68 … reme-dual.b1089

https://rog.asus.com/articles/gaming-graphics … gt-dual2dt512m/

https://m.hexus.net/tech/reviews/graphics/127 … ics-benchmarks/

This is unreleased Rage6 Maxx, it did not see daylight to the consumers like earlier Rage4 Maxx did : https://www.techpowerup.com/gpu-specs/radeon-ddr-maxx.c2326

I'd assume you'll need a board with PCIe bifurcation in order to get this running. The 16x slot needs to run in 8x/8x mode. Usually server or workstation boards can do that.

tehsiggi wrote on 2026-07-15, 18:53:

I'd assume you'll need a board with PCIe bifurcation in order to get this running. The 16x slot needs to run in 8x/8x mode. Usually server or workstation boards can do that.

Why? No other dual GPU PCIe gaming cards need bifurcation. The SLI / CFX is on the video card itself.

cyclone3d wrote on 2026-07-15, 19:24:

tehsiggi wrote on 2026-07-15, 18:53:

I'd assume you'll need a board with PCIe bifurcation in order to get this running. The 16x slot needs to run in 8x/8x mode. Usually server or workstation boards can do that.

Why? No other dual GPU PCIe gaming cards need bifurcation. The SLI / CFX is on the video card itself.

Because other cards had PCIe bridges (often from PLX) whereas this one does not if you look at the layout.

tehsiggi wrote on 2026-07-16, 04:04:

cyclone3d wrote on 2026-07-15, 19:24:

tehsiggi wrote on 2026-07-15, 18:53:

I'd assume you'll need a board with PCIe bifurcation in order to get this running. The 16x slot needs to run in 8x/8x mode. Usually server or workstation boards can do that.

Why? No other dual GPU PCIe gaming cards need bifurcation. The SLI / CFX is on the video card itself.

Because other cards had PCIe bridges (often from PLX) whereas this one does not if you look at the layout.

Ah, ok..looked it up some more and it was apparently only compatible with Nforce4 boards of the time that were able to switch to x8/x8 mode.

Yeah, I suspect any board with SLI support that uses the "manual SLI switching" approach (like flipping the small PCB on ASUS boards) will work. Basically how SLI worked on those boards was you either have the top slot at 16x running (and all 16 lanes routed through to the top slots via the selector board) or you switch to SLI mode, where the chipset does bifurcation and you'll get 2x8 lanes arranged. The small selector board will then route 8x lanes to the top and 8x lanes to the bottom slot.

If you want to run this card, I assume you'll enable "SLI" in bios (effectively enabling bifurcation 8x8x) but you'll leave the selector on single graphics card, giving you the 8x8x lanes on the top PCIe slot - exactly what that card will need.

I imagine that if you found a motherboard with the correct PCIe slot electrical layout and SLI bios license, this card should not be any harder to get running compared to a 6800GT SLI setup with two individual cards. It would appear to the system as two independent 6800GT GPUs and the stock nvidia driver should be able to enable SLI using the interconnect traces on the PCB just like an SLI bridge.

NeoG_ wrote on 2026-07-16, 07:02:

I imagine that if you found a motherboard with the correct PCIe slot electrical layout and SLI bios license, this card should not be any harder to get running compared to a 6800GT SLI setup with two individual cards. It would appear to the system as two independent 6800GT GPUs and the stock nvidia driver should be able to enable SLI using the interconnect traces on the PCB just like an SLI bridge.

Yep. I suspect there is no more magic in this card than 2 6800GTs being on the same PCB - not to talk it down, it's a beautiful card!

I think the k8n neo4 SLI I had would have been able to run the card just fine https://theretroweb.com/motherboards/s/msi-k8 … um-ms-7100-v3.x I suspect the board must be able to enable SLI through the bios explicitly..

Gigabyte had dual 6600GT card called 3d1, it was bundled with gigabyte nforce 4 sli motherborad (GA-K8N-SLI) and you had to set the sli switch to non sli mode for this card.
also their Intel nforce 4 sli motherboard came with 2 set of sli switch cards, normal/3d1 and normal/sli.

They were released to the market in very limited numbers, as far as I know. ASUS later did another batch of those with GeForce 7800GT dual (2000 cards released total). Gigabyte also released 6800GT dual which is much more compact. And Leadtek released dual 6600GT.

AFAIK you don't need Nforce 4 specifically and Nforce 5 series also will do. Maybe even newer chipset that routes slots to Nvidia NF200.

Karbist wrote on 2026-07-16, 08:45:

Gigabyte had dual 6600GT card called 3d1, it was bundled with gigabyte nforce 4 sli motherborad (GA-K8N-SLI) and you had to set the sli switch to non sli mode for this card.
also their Intel nforce 4 sli motherboard came with 2 set of sli switch cards, normal/3d1 and normal/sli.

I suspect they're using one of the connections on the switch card to enable bifurcation and the other ones just re-route the lanes.
The normal/sli does both, the normal/3d1 card does only the bifurcation toggle.

EDIT:
Just checked the MSI K8N Neo4 SLI schematic - yes, they use a GPIO pin to configure SLI. The card will either leave it floating (and the pull-up near the chipset will set it high) to enable SLI or pull it low (by connecting it to GND via the switch card) to disable SLI.

I suppose you could just tape off that particular pin and then a card like the 6800GT Dual would work on such a board. I suspect similar things on other boards to be possible too.

There's a bunch of boards that don't use a physical switch and SLI still works. Like ASUS A8N32-SLI for example. The card will only work in the lower slot though, which is connected to Nforce 4 SLI. The same probably applies to AM2 boards too (Nforce 570), which do bifurcation for SLI the same way.