Question to those with xpanders...

[licarell]

I'm thinking about getting a Cubix xpander.... Question...

If I want to use a GFX card in an xpander for my display will there be a performance hit compared to the same card plugged directly into a PCI x16 slot on the motherboard?... I only say that because if I read right the xpander card for octane is only a PCI x1... or did I read wrong...


Thanks,

Lic

[havensole]

They make a few different versions, a PCIe x1 bus system, PCIe x8 bus system, and a new PCIe x16 system. The only time you should see any lag is when the obj is initially loaded onto the GPU's. Other then that there may be a slight performance hit in Octane. Its not enough to worry about.

[licarell]

Ok I'll wait for the x16 version (didn't see it anywhere on the site)... BTW when it does come time for my purchase will refractive provide discount codes for we octane users?

Just wondering,

Lic

[ROUBAL]

I just want to make you aware about a small detail that can have some importance : Be careful if you need a graphic card with a big amount of memory : Some versions of graphic cards with more amount of memory than standard , like those GTX285 2GB made by Gainward, have big cooling pipes on the upper side (opposite to the slot) and may not fit in the Cubix Xpander.

[licarell]

Thanks for the tip... I'm using GTX 470's, I've got two but not enough PCIe x16 to go around on my MB.

My endgame is to have 3 GTX 470's in there all water cooled, should be quite the power box when I'm through.

Lic

BTW that 750w power supply should cover the 3x gtx's if thats all it's powering right?

[havensole]

The standard xpanders will only hold 2 double width gpu's like the 470. They're coming out with a rack based one that will take 6 double width or 12 single width cards. Can you imagine 12 of the new quadro 4000 gpu's? I'm not sure what the psu will be in that unit. 470s take about 220 watts each btw.

[licarell]

FYI when the GTX's are water cooled they only take up one slot per card, so yep could put 4 in there if you want.

Lic

[kivig]

I might be wrong, but this motherboard (and a few from other vendors)
http://gigabyte.com/products/product-pa ... id=3434#ov
supports up to 7(!) pci-x16 cards.
Plugged all they'll communicate with computer at 8x but that anyway should lag less than any external solution.

[ROUBAL]

FYI when the GTX's are water cooled they only take up one slot per card, so yep could put 4 in there if you want.

My own Cubix Xpander Pro 2 has only two slots... so putting 4 cards is not possible. I don't know if models with 4 slots are available. This would have to be verified with Cubix company.

Also, as said in a previous post, some water cooled cards have big pipes on the side opposed to the slot and may not fit in the Cubix box. So it is better to be careful in our choice.

[havensole]

Yeah the load lag would be roughly the same if it were physically installed in your system. This is what happens when you load the model into the gpu. You really only see a difference when using the pcie x1 bus speed version as that is 8 times slower than the x8 version and 16 times slower than the x16 version. Between the x8 and x16 the load speed difference is pretty negligible. You lose a little with the cable length, but once its on the gpu all reandering should be the same. I forgot you said you would water cool the units. They do make a four slot xpander. I think that's the xpander pro 2 if memory servers. You should be able to fit all three in if the watercooling doesn't go beyond the single wide slot configuration.
I am hoping that cubix release the special version they made for Siggraph as it looks awesome. We'll get some photos of it u and the rest of the booth in a day or so.