Power Question

[kingnothing]

I am planning to run a pair of Radeon HD 4870 cards in a CrossFire configuration. The manufacturer's website says that two of these cards is compatible with an Antec TPQ 850 power supply, but how can that be? Each card has two 6-pin power inputs, for a total of four 6-pin power connectors. The power supply has only two 6-pin power outputs. How can I connect the two power connectors from the power supply to the four total power inputs on the cards? Does each card only need one power input when run as a CF pair?

 

[bloc97]

Some websites with power supplies only calculate the watts needed and not the number of pins, so choose another power supply pehaps.

 

[kingnothing]

I was looking at AMD.com, the manufacturer of the video card. I guess AMD bought ATI. I did not know that. Anyway, they have an extensive list of power supplies by manufacturer and model. Following the link for each model of power supply shows which ATI graphics cards and how many are compatible with that power supply. It clearly says that two Radeon 4870s are compatible with with an Antec TPQ850. Given the number of power connectors, I just don't see how that is possible. Can someone please help me understand?

 

[hunter315]

According to the Antec site the TPQ 850 h as 2 6 pin PCI-E connectors and 2 6+2 pin connectors which will work as 6 pin PCI-E connectors or 8 pin PCI-E connectors giving you effective 4 6 pin PCI-E connectors and enough power for 2 4870s. The TPQ 850 has more than enough power to handle two 4870s so if you dont have enough PCI-E connectors you should have gotten molex to 6 pin adapters with the cards, you can use those without a problem

AMD has owned ATI for a few years now, its just now they are phasing out ATI, it used to have its own site but now its all AMD which makes it a bit more obvious.

 

[kingnothing]

Thanks Hunter. I went to Antec's website and took a closer look and found that it does have two 6-pin AND two 6+2-pin power outputs.