dual 660 ti psu?

[dragantoe]

I'm trying to get a power supply for my dual 660 ti's but it seems that they get too expensive above 700W and was wondering what the minimum required power supply would be

 

[dave_the_nerd]

Depends on what the rest of your system draws.

The 660Ti's draw ~150W apiece at load. Add in your CPU's TDP, add 50w for your motherboard/RAM and 10w per HDD or SSD.

Add 50w for fudge-space if you're running a higher-end AMD CPU. (Some of them can draw more than officially rated power.)

Multiply x1.5 if you're overclocking.

Then multiply THAT total x1.25.

That's, imo, "safe" wattage for a PSU purchase. Other people might have different rules of thumb. *shrug*

 

[lehtv]

Other people might have different rules of thumb. *shrug*

If (1) the power supply is from a reliable manufacturer and (2) the wattage rating reflects its maximum continuous load and (3) it has the necessary PCIe connectors for the graphics card(s), then it's good for running the system at stock. With overclocking, add 50W-100W per GPU or CPU.

 

[dragantoe]

If (1) the power supply is from a reliable manufacturer and (2) the wattage rating reflects its maximum continuous load and (3) it has the necessary PCIe connectors for the graphics card(s), then it's good for running the system at stock. With overclocking, add 50W-100W per GPU or CPU.

soo like what wattage?

 

[lehtv]

650-850, depends on the unit and whether/how much you OC. Not all 650W units have four PCIe connectors, some do.

Out of curiosity, what is your CPU

 

[dragantoe]

Out of curiosity, what is your CPU

Xeon L5639, I was one of the first on that popular thread to get one. It's overclocked to 4 ghz. I also have 3 hard drives and an ssd, 8gb ram and an x58 sabertooth motherboard

I shud put my rig back in my sig...

 

[lehtv]

OK. That's pretty power hungry. Get 750W, even 850W if you OC the graphics cards. Newegg has Seasonic 760W Platinum for $110 AR AP. It's a great long term purchase.

If you're seriously short on cash, I'm wondering what you're doing with two graphics cards to begin with. But here's a unit that should power them: Corsair CX750M $60 AR AP

 

[dragantoe]

OK. That's pretty power hungry. Get 750W, even 850W if you OC the graphics cards.

damn, but how much wattage does the 660 ti use?

 

[lehtv]

it could be a good idea to buy a kill-a-watt and measure power consumption at full CPU load using your current power supply. I'm unsure exactly how much power the Xeon consumes at 4GHz and whether 850W would be a better idea than 750W.

damn, but how much wattage does the 660 ti use?

dave_the_nerd already told you, around 150W maximum at stock. Assuming the Xeon consumes 200W at full load, that would put full system load at about 550W without overclocking the cards. With overclocking, over 600W

 

[dragantoe]

dave_the_nerd already told you, around 150W maximum at stock. Assuming the Xeon consumes 200W at full load, that would put full system load at about 550W without overclocking the cards. With overclocking, over 600W

ok, well if I'm able to power this overclocked 660 ti with a 520W psu now, adding 200W would make it around 700W+ like you said. What's the cheapest (reliable) 700W psu?

 

[VirtualLarry]

What's the cheapest (reliable) 700W psu?

http://www.newegg.com/Product/Produc...82E16817182073

 

[lehtv]

http://www.newegg.com/Product/Produc...82E16817182073

That's definitely not the cheapest reliable 700W+ PSU. It's a rather high end unit with 7 year warranty, Gold efficiency etc. Not only that, but it would make no sense to get a Capstone as long as the Seasonic 760W Platinum is available for $110 AR AP.

That Seasonic is the best long term purchase you can make, and if you can't afford it... as I said - I don't know what you're doing having two graphics cards to begin with.

To answer your question directly, the CX750M I posted is the cheapest reliable 750W unit at the moment at only $60 AR AP. But I still recommend the Seasonic.

 

[dragantoe]

are these more reliable than the EVGA supernova?
http://www.newegg.com/Product/Produc...82E16817438007

I see a lot of people using these so I assume they're not bad

 

[lehtv]

That's a pretty decent unit. On par with CX750M. In terms of performance, it's nowhere near Seasonic, but it's packed with quite a lot of features (5yr warranty, japanese caps, modular) and quite a lot of +12V amps for what it costs. Compared to the seasonic 760W, you save $42 after shipping but lose Seasonic quality, two years of warranty, and 6-7% of efficiency. And you will lose a few bucks a year in electricity costs... exactly how much depends on how much you use the PC and what your electricity costs. E.g. with a modest 1 kW per day and a modest 0.1$ / kWh, you will lose about $2 per year with Bronze efficiency versus Platinum.

 

[dragantoe]

I have this one bookmarked, it's 80 plus silver, 750W and modular, any reason I shoudn't get it over the others?

 

[lehtv]

Nice find, go for it.

 

[dragantoe]

If anyone is still wondering, my bestbuy was having a sale on the Corsair CX750 (clearance I think), so I got a 750W, modular psu for $60, only $10 more than what I was trying to spend on a used one!
So, seems to be working, but it's pretty noisy when it boots up...