7950 Crossfire with TX 650 V1

[blacblu]

Can a TX650 V1 power a 7950 Crossfire setup with a i5 2500K @ 4.5Ghz?

 

[Alz_D]

http://www.guru3d.com/articles_pages/radeon_hd_7950_crossfire_review_2_and_3_way,5.html

Recommends a 700watt minimum for xfire.

 

[Drangueos]

Can a TX650 V1 power a 7950 Crossfire setup with a i5 2500K @ 4.5Ghz?

short answer = yes

I have an I7 [email protected] and 2x 7950 and it uses less than 600W from the wall, so from the PSU would be around 500W.

Overclocking the cards uses 700W from the wall, so tops will be 600W from the psu when overclocking everthing.

 

[tribz]

I'm not sure what you mean from the PSU? Surely if your pulling 700w from the wall, you need a 700 plus PSU ... or is it just the way your wording it that's making me read it wrong?

OP with an o/c setup, I'd say you need a bit more. My setup draws 660 from the wall when the GPUS are folding/mining.

 

[Drangueos]

I'm not sure what you mean from the PSU? Surely if your pulling 700w from the wall, you need a 700 plus PSU ... or is it just the way your wording it that's making me read it wrong?

OP with an o/c setup, I'd say you need a bit more. My setup draws 660 from the wall when the GPUS are folding/mining.

No, If you are pulling 700W from the wall, your PC is using something around 580/600W, 100W+ is lost as heat.
his psu is made to provide 650W to the PC, but from the wall it will always be more.

An example a 850W PSU full loaded at 850W can pull 1000W from the wall.

 

[Drangueos]

here is an example of my PSU a Corsair TX850 v2,
you can see that at full loaded at 852W it is pulling 1054W from the wall.

You can read more here:
http://www.hardocp.com/article/2011/08/29/corsair_enthusiast_series_tx850_v2_psu_review/1

 

[tribz]

Interesting. Is that where the effeciency rating comes into play then?

So an 875w PSU (like mine) will always be able to deliver 875w to the components but will draw as much as a 1kw from the wall depending on efficiency?

 

[Drangueos]

Interesting. Is that where the effeciency rating comes into play then?

So an 875w PSU (like mine) will always be able to deliver 875w to the components but will draw as much as a 1kw from the wall depending on efficiency?

Yes and yes

 

[blacblu]

So, can I safely buy them without having to change my PSU, even if it's some of those "Boost" or overclocked models?

 

[thefogo]

It probably could, but it only seems to have 2 pci-e connectors.
Unless I'm looking at the wrong one.

 

[spixelspixel]

In my 5 minute use of a 7950 boost before I returned it, it used 180w max at stock during heaven benchmark. Much more power efficient than I expected. My gtx 670 was around 215w.

 

[Drangueos]

So, can I safely buy them without having to change my PSU, even if it's some of those "Boost" or overclocked models?

yes...

 

[Drangueos]

It probably could, but it only seems to have 2 pci-e connectors.
Unless I'm looking at the wrong one.

he will need to use the adaptors, but the psu will handle the power.

 

[blacblu]

Thanks for the info, guys.

 

[Marine-RX179]

One thing though, while the PSU's output may be capable enough for your system, but you might still end up needing to upgrade the PSU due to the noise of the fan when stressed so close to 90-100% load.

For example, I once ran a system with a Q6600 overclocked to 3.6GHz on 1.5v vcore and overclocked 5850...and despite my trusty Corsair CX400 (Seasonic unit) was more than capable and up for the task, the fan was spinning at such a high rpm and it's noisy like a chopper is taking off

I think there's no harm in trying the Crossfire setup with your current system and PSU, but just giving you a heads-up about the possible noise issue.

 

[tribz]

Yes, I had a corsair Hx1050 that did that. Blooming annoying for a 160 quid PSU.

 

[krooton]

I ran my 7950 with an OC'd 2500k on a 520w PSU, and I don't see adding another 7950 bumping up my wattage by 230w, so I would say yes to the OP.

 

[Calin Banc]

2500k@3,3GHz + 8GB RAM + @5fans (including the one from CPU) + 2HDD + 7950@900MHz/1250Mhz/1,081v takes around 280-290W from the wall. With CPU@4,5GHz and 7950@1170/1600/1,2v it goes as high as 380-390W+ from the wall.

So, @stock values for GPUs you should be ok, but for OC you'll need to keep it in check or buying at least a 850W power unit for "future proofing".

 

[spixelspixel]

2500k@3,3GHz + 8GB RAM + @5fans (including the one from CPU) + 2HDD + 7950@900MHz/1250Mhz/1,081v takes around 280-290W from the wall. With CPU@4,5GHz and 7950@1170/1600/1,2v it goes as high as 380-390W+ from the wall.

So, @stock values for GPUs you should be ok, but for OC you'll need to keep it in check or buying at least a 850W power unit for "future proofing".

That's really high power consumption for a 2500k and 7950 even overclocked to the max.

What power supply do you have and how did you test to get those numbers?

 

[Drangueos]

2500k@3,3GHz + 8GB RAM + @5fans (including the one from CPU) + 2HDD + 7950@900MHz/1250Mhz/1,081v takes around 280-290W from the wall. With CPU@4,5GHz and 7950@1170/1600/1,2v it goes as high as 380-390W+ from the wall.

So, @stock values for GPUs you should be ok, but for OC you'll need to keep it in check or buying at least a 850W power unit for "future proofing".

if yours overclocked goes up to lets say 400W... 150W is the system and 250W the graphics.

so 2 graphics would be 500W + 150W from the system = 650W from the wall and this will be 550W from the PSU... so he still OK, even overclocking.

Like I said mine tops at 660W from the wall (i7 [email protected] and 2x 7950 1100/1500, also I have 3 HDs, 3 SSDs, 8x 120mm fans, 3x 140mm fans and a fan controller.
Even 700W from the wall will be less than 600W from the PSU.