3rd GTX 480 not showing up in Device Manager

[UrbanSmooth]

Hello.

I have three GTX 480s in 3-way SLI connected via the 3-Way SLI bridge. All three are water cooled and connected to the ASUS Rampage III Extreme motherboard. I am using an AX1200 PSU. One of the 480s is not showing up in Device Manager. I am using Windows 7 64-bit and the latest Nvidia Drivers (266.58) All three GPUs are plugged in and ready to go, all except one. This one is in PCI-E slot #3 (starting from the top). I know that it's powered-on because the LED on the Koolance waterblock, which plugs into the GTX 480's fan plugin, is lighting up. Any ideas? Thanks.

[Hondacity]

use the pcie lane switches...

[UrbanSmooth]

All four are set to 'ON.'

[Hondacity]

check one by one?

[UrbanSmooth]

I know that it's the bottom one. I had each of my three monitors plugged into each of my three GTX 480s. The bottom 480's monitor was not displaying anything.

[Hondacity]

re-insert gpu#3?

[UrbanSmooth]

Ouch, going to have to drain the loop to do that...

[Hondacity]

you can re-insert 3 gpus...if you have 3 hands

[OgaiB]

Hello.

I have three GTX 480s in 3-way SLI connected via the 3-Way SLI bridge. All three are water cooled and connected to the ASUS Rampage III Extreme motherboard. I am using an AX1200 PSU. One of the 480s is not showing up in Device Manager. I am using Windows 7 64-bit and the latest Nvidia Drivers (266.58) All three GPUs are plugged in and ready to go, all except one. This one is in PCI-E slot #3 (starting from the top). I know that it's powered-on because the LED on the Koolance waterblock, which plugs into the GTX 480's fan plugin, is lighting up. Any ideas? Thanks.

Increase memory LowGap in BIOS above 2048MB

[AquaRelliux]

Have u plugged in the additional 4 pin conectors on the motherboard?(there is 2 of them)

//Aqua

[UrbanSmooth]

Increase memory LowGap in BIOS above 2048MB

Explain in more detail, please.

Have u plugged in the additional 4 pin conectors on the motherboard?(there is 2 of them)

//Aqua

The AX1200 doesn't give me enough molex cables to the plug the middle 4-pin molex connector in. I have the bottom one connected, but, not the middle one above the first PCI-e lane, near the CPU. Will this make a difference? I thought it just provided extra power for extreme overclocking.

[OgaiB]

Explain in more detail, please.

Go to the bios. Find: "Memory feature" -> "Memory Low Gap" and set it above 2048MB

[PatRaceTin]

did you try reformatting an installing new fresh windows ?

[TJ TRICHEESE]

Maybe this will help? Heres a link to the Nvidia surround page:http://www.nvidia.com/object/3dv-sys...echnology.html

[UrbanSmooth]

Go to the bios. Find: "Memory feature" -> "Memory Low Gap" and set it above 2048MB

Thanks.

did you try reformatting an installing new fresh windows ?

Yep.

Maybe this will help? Heres a link to the Nvidia surround page:http://www.nvidia.com/object/3dv-sys...echnology.html

I'm well aware of what I need, thanks.

Well, it looks like I've run into power issues now. My circuit is fine, it's just that when I try to turn my new system on, it will fire up for a split second, and then die to nothing. Motherboard still works in 'off' mode with certain lights on, yet, not powered up. Perhaps the PSU is faulty?

[UrbanSmooth]

Switched from the AX1200 to two HX1000s. Works just fine. I had to short the 24-pin mobo connector of one of the HX1000s and use the extra PCI-E connectors to power the GPUs. Using the PCI-E connectors on the rail that you short (in this case, the one with the 24-pin mobo connector), will not provide power to the GPUs. This was throwing me off, but is well fixed now!