People keep asking me about what to do for their first rig etc. so I'm going to outline it quickly here and make it easy for everyone.
I recommended non-powered (regular) x16 --> x16 extenders and three cards per board. I've run rigs like this for months on end with no problems (no motherboards frying etc)
Stuff needed: (intel build)
3x pcie x16 motherboard eg
http://www.newegg.ca/Product/Product.aspx?Item=N82E16813157295celeron cpu eg
http://www.newegg.ca/Product/Product.aspx?Item=N82E168191164098 gb ddr3 ram (2x 4gb) eg
http://www.newegg.ca/Product/Product.aspx?Item=N82E168201042621 sata hdd eg
http://www.newegg.ca/Product/Product.aspx?Item=N82E168221365913x non powered x16 extenders from ebay eg
http://www.ebay.com/itm/New-PCI-E-Express-x16-Extender-Flexible-Ribbon-Cable-/281070938954?pt=LH_DefaultDomain_0&hash=item4171222b4a1x wifi adapter (any, usually usb) if needed
gold or platinum 850w psu eg
http://www.newegg.ca/Product/Product.aspx?Item=N82E168171390113x 7950s (MSI and Sapphire are some of the few non-volt locked ones right now)
http://www.newegg.ca/Product/Product.aspx?Item=N82E16814127667Build is the same for amd, just use a board with 3x pcie x16 slots and a cheap cpu
Then, buy this from home depot:
2x plastic crates
small wood or metal screws that are pointed, about 1.5-2.0 cm long and are small enough to go in the GPU plate holes
2 ft ruler shaped flat piece of steel (they sell this in 4 ft I think, you need to cut them in half with a hack saw)
vinyl stick on cushions
http://www.homedepot.ca/product/1-2-clear-vinyl-pads-surface-gard/948073--> $10 for a case
Put the vinyl cushions on the bottom of one of the crates. Put the motherboard on top of the cushions.
Put the PSU in the other crate. Add RAM/CPU. Hook up the PSU to everything.
Insert the extenders and plug in the hard drive.
Put the cards on, screwing them into the inner lip of the plastic crate and bracing them with the flat piece of metal you bought as a cross member towards the end of the card.
Plug the card into the extender and connect remaining power bits.
Turn rig on by shorting the power pins on the motherboard with a screwdriver, then set the motherboard to turn on as soon as power is given to it ("Wake on power" option in BIOS).
Install Windows (use a USB drive or connect a SATA DVD Drive temporarily), mine (I use guiminer-scrypt).
This is what it looks like:
![](https://ip.bitcointalk.org/?u=https%3A%2F%2Fi.imgur.com%2F6NZkn0P.jpg&t=665&c=qWNsNRCU1wGpmw)
Rig power consumption at 1.8 MH/s is ~750 watts in summer or ~650 watts in winter.