PCIe 1x to 16x adapter

[Joeysaurr]

I was just wondering if in theory I could run a graphics card on the 1x slot on my motherboard using an adapter. I understand the bottleneck it would be causing but it would be in a system that will only have a dedicated graphics card in it to offload a bit of work from the CPU.

 

[SkyBill40]

Not the least bit likely. That slot just doesn't have the bandwidth capability.

 

[noidea_77]

In theory you don't need an adapter if the x16 area behind the x1 slot is clean. Beside that it will not offload anything from the cpu.

 

[Rookie_MIB]

There are two ways around that problem, and I have done it before. Please note, this will definitely void the warranty on your motherboard, so proceed at your own risk.

If you look around at different PCI-e slots, especially shorter ones, you'll notice that some are what you would call, 'open ended'. In other words, the back side of the slot is cleared out, and would allow a longer card in, although it will hang off the end and only be supported by the front of the card and the retaining screw. If your x1 slot is not open ended, VERY CAREFUL work with a dremel and an exacto knife can remove that back piece so that you can fit a longer card in there. This shows the net result, but obviously, again, BE CAREFUL.

http://blog.zorinaq.com/?e=53

Another solution is that they do make what is called a 'flexible riser' and sell those in various places (eBay, newegg, etc), what it is - a pci-e hard piece like what you would find on the bottom of your pci-e card with the metal traces in various sizes from 1x to 16x, leading to a ribbon cable, which terminates in a pci-e plastic slot which clips to the bottom of the card. You can then mount the card in any open slot where the mobo wouldn't interfere. So - if you have an m-atx board in a full atx case, you can mount the card in the bottom slots, and run the cable to any open pci-e slot. Nice thing is no voiding the warranty, but you have to buy the adapter.

For those saying that the bandwidth isn't sufficient, that isn't true if it's being used for offloading CPU work - such as bitcoin mining or folding@home. Many people have been more than successful doing that on an x1 slot.

 

[SkyBill40]

An X1 slot doesn't have the same flow through as an X16 slot. No matter what the purpose it's being used for, you simply cannot argue that fact.

 

[Rookie_MIB]

No, not arguing that it just doesn't have enough bandwidth to do much -graphically-. No doubt, the bandwidth required for a reasonably powerful graphics card is much higher than what an x1 (and almost an x4) can provide. However, when using it as a GPGPU (as I said for bitcoining and other specialized computing work) it is a viable solution.

Also, if he -is- going to use it for a GPU, there is a site that actually tested the theory. About the best performance comes at the level of the HD5850 or lower. Using it in a x1 gen 2.0 slot it achieved about 75% the performance of a x16 gen 2.0 slot. Not bad, but anything more powerful will (as you mentioned) quickly swamp the x1 slot. A HD5850 in a x4 2.0 slot actually hit 95% capability of the x16 slot.

I guess ultimately the big question is what the application is? Just something better than the IGP? Something to fit in a SFF which might only have an x1 slot available (like my ASRock Q1900 boards?)? He said it was to offload some of the work from the CPU...