PCI-E riser vs external pci-e expansion case - differences?

[grepawking]

I see that risers can be purchased for fairly little $$ and can be up to about 15" - they are available in all 4 speeds.

I also see external pci-e expansion cases which are a pci-e card with a port on the back, cable, and external case. These are like $400-$1,000 for a single port!

Since the slot delivers everything the card needs to run (except very power hungry graphics & co-processor cards), Is there a way to extend the slot with a cable that extends outside of the case and maybe into an external case where a slot is mounted (for cards that need a minimum of power)? I know EMI is an issue, so a shielded cable is necessary.

Is this doable and if not, what is the best way to extend a pci-e slot outside a case by maybe 1 meter?

 

[Yuriman]

I haven't looked into risers since the AGP days, but there were limitations on trace length. A 2cm riser is probably no big deal, but I'd be somewhat surprised if a video card even booted 1 meter away. I don't think it's interference, so much as signal integrity.

 

[grepawking]

I haven't looked into risers since the AGP days, but there were limitations on trace length. A 2cm riser is probably no big deal, but I'd be somewhat surprised if a video card even booted 1 meter away. I don't think it's interference, so much as signal integrity.

I agree with you on the signal integrity part. But here is the question, if these external cases are available for $500-$8,000, and are connected via a cable, I would think that a good cable (lower/thicker gauge & shielded) carrying the signal data should be able to get past the 8-12" limit. I would even go as far as adding an external power source wired into the external enclosure for the 12 & 3.3v on the card.



These are two good links to see what the larger systems look like:
http://magma.com/products/pcie-expansion/expressbox-2200/

It looks like this unit uses a DVI-i cable to transmit the data. It has a card that has a backpane with a DVI-I connector.
www.startech.com/Cards-Adapters/Slot-Extension/PCI-Express-to-2-PCI-Full-Length-2-PCIe-Single-lane-Expansion-Box~PEX2PCIE4L

These sites sell some pretty high end stuff. The external pci-e cables for the systems below are available up to 7 meters!

http://www.onestopsystems.com/desktop-pcie-enclosures

http://magma.com/products/pcie-expansion/

 

[PhIlLy ChEeSe]

How bout something like this and use a longer cable, as stated you'll lose signal integrity after so much.
http://www.ebay.com/itm/PCI-E-1x-to...m-USB-Cable-/321336495572?hash=item4ad125cdd4