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Crossfire HD 6950 PSU Help

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February 15, 2013 1:05:24 AM

Sorry if something similar has been asked before, but I was wondering if my current PSU would be capable enough to handle 2 HD 6950's.

CPU: AMD Phenom II 970 BE @ 3.5
Both cards would be an xfx double D stock version of the HD 6950
PSU: http://www.newegg.com/Product/Product.aspx?Item=N82E168...

700W with 2 12v rails: each at 28A for a total of 648 watts

More about : crossfire 6950 psu

February 15, 2013 1:18:17 AM

Sorry forgot to add that I already bought the other 6950 :p , it's shipping as we type. Also, I just updated my signature to have my system specs if that helps at all (I was using the older version of my computer for the signature which had an HD 4870 in it lol)
a c 1105 ) Power supply
February 15, 2013 5:02:42 AM

For a system using two Radeon HD 6950 graphics cards in 2-way CrossFireX mode AMD specifies a minimum of an 700 Watt or greater system power supply. The power supply should also have a maximum combined +12 Volt continuous current rating of 48 Amps or greater and have at least four 6-pin PCI Express supplementary power connectors.

Total Power Supply Wattage is NOT the crucial factor in power supply selection!!! Sufficient Total Combined Continuous Power/Current Available on the +12V Rail(s) rated at 45°C - 50°C ambient temperature, is the most critical factor.

Overclocking of the CPU and/or GPU(s) will require an additional increase to the maximum combined +12 Volt continuous current ratings, recommended above, to meet the increase in power required for the overclock. The additional amount required will depend on the magnitude of the overclock being attempted.

You may find power supplies on the market that supply more than enough Wattage to run the system. However, some of them lack Sufficient Amperage capacity on the critical +12 Volt rail, which is necessary to properly power the critical components in the system (i.e. CPU and GPUs). This is the reason why graphics card manufacturers may overstate the power supply wattage, usually by at least 50 Watts, in an attempt to take into account some of those power supplies that have the weaker +12 Volt rail(s).

The Rosewill Value II Series 700W (RV2-700), with its maximum combined +12 Volt continuous current rating of 54 Amps and with one 6-pin and one (6+2)-pin PCI Express supplementary power connectors, is theoretically electrically sufficient to power your system configuration with two Radeon HD 6950 graphics cards in 2-way CrossFireX mode but it is deficient by two PCI Express supplementary power connectors so you will have to resort to using a couple of dual 4-pin Molex peripheral to 6-pin PCIe adapter cables.

That power supply model has a terrible reliability reputation so it may just burn out. May also explain its very short one year warranty period. Seems Rosewill doesn't even put much faith in that product.
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a c 260 ) Power supply
February 15, 2013 12:02:16 PM

strohmz said:
Alright, Thank you.

I guess I will buy another PSU, will a Corsair 750W (http://www.newegg.com/Product/Product.aspx?Item=N82E168...) do or should I get the higher 850W (http://www.newegg.com/Product/Product.aspx?Item=N82E168...) one with more amps on it? Also, if anyone knows any good deals on psu's, then I'm listening.



Hi - Rosewill has some good/very good psu's these days,
(Capstone/Fortress/Tachion series) but that is an older
& not very good model(why it is discontinued). You need a quality 700w to run a sys
with 2 6950's in CF.

So, your own 750w suggestion is fine and has the requisite 4 pci-e connectors
to run 2 6950's in CF.
a c 1105 ) Power supply
February 15, 2013 4:20:28 PM

strohmz said:
Alright, Thank you.

I guess I will buy another PSU, will a Corsair 750W (http://www.newegg.com/Product/Product.aspx?Item=N82E168...) do or should I get the higher 850W (http://www.newegg.com/Product/Product.aspx?Item=N82E168...) one with more amps on it? Also, if anyone knows any good deals on psu's, then I'm listening.

The Corsair Enthusiast Series TX750 V2 (SKU# CMPSU-750TXV2), with its maximum combined +12 Volt continuous current rating of 62 Amps and with four (6+2)-pin PCI Express supplementary power connectors, is more than sufficient to power your system configuration with two Radeon HD 6950 graphics cards in 2-way CrossFireX mode. This PSU model uses Seasonic as its OEM.

The Corsair Enthusiast Series Modular TX850M (SKU# CP-9020004-NA / CMPSU-850TXM), with its maximum combined +12 Volt continuous current rating of 70 Amps and with four (6+2)-pin PCI Express supplementary power connectors, is way more than sufficient to power your system configuration with two Radeon HD 6950 graphics cards in 2-way CrossFireX mode. This PSU model uses CWT (Channel Well Technology) as its OEM.

Either PSU is more than sufficient for your system configuration.
a c 260 ) Power supply
February 15, 2013 4:37:41 PM

The 750 v2 ko888 rated above is the one I linked, and is $23 less
than the other 750.
a c 1105 ) Power supply
February 15, 2013 5:17:17 PM

toyftw said:
The 750 v2 ko888 rated above is the one I linked, and is $23 less
than the other 750.

@strohmz linked to the newer model Corsair Enthusiast Series TX750 (SKU# 75-001309 / CP-9020042) made by Chicony Power Technology. All of the customer reviews on that web page indicate that they reused the original V1 model page contents with a few modifications. If you look at the picture of the PSU label it is for the newest Chicony made model.

The Corsair Enthusiast Series TX750 V2 (SKU# CMPSU-750TXV2) model is now discontinued and is being cleared out of the distribution channel hence its lower price.
a c 260 ) Power supply
February 15, 2013 5:26:31 PM

ko888 said:
@strohmz linked to the newer model Corsair Enthusiast Series TX750 (SKU# 75-001309 / CP-9020042) made by Chicony Power Technology.

The Corsair Enthusiast Series TX750 V2 (SKU# CMPSU-750TXV2) model is now discontinued and is being cleared out of the distribution channel hence its lower price.


right ko - he did link the newer model - I linked the
750 v2
and aware they are clearing it out, but was suggesting
strohmz get the same perf for $23 less, you happened to rate
the v2 version, so just reminded him he could save $23.
February 15, 2013 8:34:57 PM

Thank you guys, sorry for long reply but was at work, I guess I will check out the v2 before they go off the selves.
February 15, 2013 8:34:59 PM

Thank you guys, sorry for long reply but was at work, I guess I will check out the v2 before they go off the selves.
February 15, 2013 8:35:04 PM

Thank you guys, sorry for long reply but was at work, I guess I will check out the v2 before they go off the selves.
a c 260 ) Power supply
February 15, 2013 8:50:36 PM

strohmz said:
Thank you guys, sorry for long reply but was at work, I guess I will check out the v2 before they go off the selves.


The v2 is Seasonic built(with several good reviews), the Chicony built unit doesn't
have a lab review yet. I'm sure Corsair spec'd it well, but
would still like to see a review.
February 15, 2013 8:52:19 PM

Sorry for the reposts, Chrome messed up my internet.
!