This may sound tough, but hopefully you received the video card with software and an instruction manual. You might want to open the instruction manual and see what it says, sometimes important directions on installing and using the video card will be addressed, and you won't have to ask the rest of to do the ground work YOU should have already done...
? what? I'm not asking for installation instruction I'm asking about the power cord that connects the GC to the PSI. It has 3 pins while PSI cord has 4 holes. The instruction manual only provides a quick install guide that is very short.
The only 3 pin connectors I know of in use on the internals of a computer are fan connectors, and they look drastically different, and couldn't power a GPU if they tried. You're mistaking something for something else.
Some power supplies (older) do not have the connector required to connect the power supply (PSU) to the Video Card (GPU).
The end of harness with 6pin connector plugs into the end of the Video Card. The other end plugs into one of the moldex connectors on the harness coming from your PSU.
Does the connector you have look something like this? http://www.newegg.com/Product/ShowImage.aspx?Image=12-8...
so thats the adapter allright.
So your psu doesn't have PCIe power connectors that would fit straight into the power connector on the card?
and the card only needs 12V and ground via the adapter from the molex connector that also has pins for 5V and another ground. The PCIe power connector has 3 ground pins and 3 12V pins, that adapter just couples these with the ones on the molex