Is it possible to use PCI-e dual risers to run double the amount of cards?

[calaber24p]

I have a motherboard with 4 pci- slots and I was wondering if it was possible to connect 4 pci-e to dual pci-e risers, in order to increase the amount of possible GPUS to 8. This is the riser I am talking about and I would purchase 4 of them.

 http://www.amazon.com/Supermicro-RSC-R2UT-2E8R-RISER-PASSIVE-2-PCIE/dp/B0037KAE2O/ref=sr_1_2?s=electronics&ie=UTF8&qid=1386157139&sr=1-2&keywords=2x+pci-e+

In addition I would add pci-e riser extensions on each of the cards in order to connect to my cards mounted above the MB. What would some potential problems with this setup be ? If I have enough power to run the cards would this setup work?

Thanks in advance.

[vapourminer]

it might work but only on slots that are electrically 16 lanes.

so if your mobo has 4 pcie slots, all physically 16 lanes (full size) but electrically  only 2 are 16 and 2 are 8 you can only use this card on the 2 16 lane slots.

[bitminer9000]

Be careful, that isn't a passthrough riser. Unless you have the supermicro mobo that is made for that riser then from my experience It may work, it may not work, or a capacitor will blow on the mobo.
good luck.