I am planning to use nVidia 750 Ti cards in my rig, which don't actually require any power other than that from the PCI-E slot.

I would like to ask, how do risers work?

I have seen the followng on ebay:

http://www.ebay.co.uk/itm/PCI-E-Express-x1-to-x16-Adapter-Extender-Cable-Riser-Card-Mining-Cooling-bitcoin-/251461244051?_trksid=p2054897.l4275

for only £6.99, you get a 26 cm x1 to x16 riser cable....

Here are my questions

1. Will this work wth my 750 Ti

2. How much Khash will this reduce from my 750 Ti, if any? It is said to do 273 Khashes on its default settings, with no overclocking etc

3. If I got a powered riser, would this remove any issues with reducing the Khashes

4. How do powered risers work? Are they powered by USB, or are they powered by 6-pin or 4-pin PSU connectors, or what?

Thanks