How to connect my GPU???

[intel_g630]

Got a new used Sapphire hd 6770. Core clock 775Mhz
Now what I need to know is:

1. The card has a 4-pin power connector. The power connector has only three wires i.e one yellow and two black, so is it normal or is the connector damaged?

2. My PSU has two 4-pin connector free one of which is with the SATA power cable, so where do I connect the power connector? (A three pin to a four pin???)

3. Any online tutorial for installing the GPU will be greatly appreciated.

 

[geofelt]

You have a very strange 6770. Normally, the power connector on a 6770 is a 6 pin pci-e power connector.
Your psu should be at least a 450w unit, and that will normally have a 6 pin pci-e connector that you should use.
If it does not have at least one 6 pin connector, you could use a 4 pin molex to 6 pin adapter.
It will look like this:
http://www.newegg.com/Product/Product.aspx?Item=N82E16812887001

Without a 6 pin cable available, it is possible that your psu is a cheap one that can not deliver the necessary 450w.