PSU ?

[Niklas_13]

I see alot recommend a Corsair 750 PSU for xfire - Sli setups. Now taking that a GTX 275 recommends a 40a 12v rail, useing sli would need a PSU with 80a 12v rail or a few rails of 12v120 so on to = 80amps. Or is it 40amps for the PSU and whole system ?

Thanks all

 

[lucuis]

The amp recommended figure is for the entire system, and is grossly overstated. The max a single GPU can use right now it 300watts, or 25amps. That would leave 180watts for the rest of the system.

Here's a list of graphics power consumption when the GPU is idling and under full load. Notice the gtx 275 system only uses 251watts for the ENTIRE system!
http://www.tomshardware.com/reviews/geforce-gtx-275,2266-14.html

The Corsair 750w PSU will do superbly for an SLI/CF system.

 

[Proximon]

Well said.

I would call the 750TX the budget choice for GTX 275 SLI, and the 850TX a nice upgrade from that.

 

[Niklas_13]

thanks for the info guys, This being said what would be a better chose for a sli/xfire setup

1 Corsairs 850 with 1 70amp rail http://www.newegg.com/Product/Product.aspx?Item=N82E16817139009

2 Antecs truepower new 750 with 100amps on 4 rails http://www.newegg.com/Product/Product.aspx?Item=N82E16817371025

So more amps or more watts

 

[jsc]

Sigh. Think about this: how can a 750 watt PSU put out 100 amps at 12 volts (1200 watts total)?

You need to learn to read labels and specifications better. If you look at the picture of the label of the PSU, you will see 4 rails, each with a maximum of 25 amps. But the next line below says 62 amps total.

So the answer to "So more amps or more watts ?" is "Yes. Corsair 850."

 

[Proximon]

Or to put it another way, the amps you see associated with multiple rails are just for protection. They are not additive.

Usually on a label you will see a wattage figure for all the 12V rails. Divide this by 12 and you have the amps.

 

[Niklas_13]

Thanks for the helps guys and clearing this up for me!!!