Need opinions on PSU

3Ball

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Hello all,

I recently built a system for a friend of mine. The specs are as follows:

Antec 300 (4 case fans)
2x7200rpm HDD's
Single DVD Burner
4gb (2x2gb) OCZ DDR3 12800
EVGA Superclocked GTX275
ASUS P7P55D PRO Mobo
Core i-7 860 @ 3.6ghz (1.35v...trust me, it needs this much) w/ zalman cnps 10x quiet cpu cooler
Creative X-Fi sound card
Wireless add-in card
PC-Power and Cooling 610w psu

Now here is the issue. He is going to be adding another 4gb of ram at some point, and quite soon will be adding a 2nd GTX275 (he will be getting it for $40, so this is not going to change). Between myself and another friend of his we believe he needs to take two different paths for the PSU, and so I felt that you guys should help out. I am in favor of the Corsair TX850w and he is in favor of the HX750w.

Now I fully understand that the HX series is higher quality...even though it is a modular power supply. Though the TX series is no slouch. IMO he could run a 750w psu and run the system fine, but would be straddling the line of around 70% of the psu at load. I get these numbers from reviews of similar setups and just an estimate of what his system will draw.

His system, with the OC, and soon to be running 2xGTX 275's, which will probably be slightly OC'd as well will roughly take up 500 - 550w of power during load. The HX750w would be rated at peak wattage of 750w (naturally), but actual normal rated usage being somewhere along the lines of 735 - 740w.

This now leads us to load percentage (as I am sure many of us would agree both), he will want to run anywhere form 60 - 80% load on his PSU at MAX scenario, so lets take a middle of the ball park area on load % and say 70%. Now we take the upper-limit of normal usage and say 740w multiplied by the .70% and arrive at 518w, right about where his system will be running. (this seems best case scenario to me)

This doesn't leave whole lot of room for more powerful components and extra hard drives when the time comes imo. So here is what I said: I would be at better ease of mind if the system ran on the TX850w and would leave him room to grow (more HDD's, mem, more power hungry GPU's,etc...), even though I agree that the system would function well enough on the HX750w.

But lets say we take the scenario ruling against my decision, and the HX750w is chosen. Wouldn't it then be a better purchase to just go ahead and get the TX950w over the HX750w as they are the same price? I will link them below. If I am completely off base then let me know. I understand that the system by no means needs the 950w. So I ask you, what would you recommend? If ruling against the TX850w, would it then still be more wise to choose the TX950w over the HX750w? Thanks in advance to all!

HX750w: http://www.newegg.com/Product/Product.aspx?Item=N82E16817139010

TX950w: http://www.newegg.com/Product/Product.aspx?Item=N82E16817139013

Best,

3Ball

 
Basically it comes to if the person cares about power draw and his monthly bill or not.
The 750 will be better since it is 80+ silver certified. It will be more efficient at a wider range of power draws.
The 950 is still good but will be a bit less.

If he doesn't care, why bother with the 750 since they are the same price? Besides, then he will have the power for a pair of radeon 5970s in crossfire with an overclocked i7 980x.

Just to note, the main draws will be the Graphics card and the CPU. HDDs add maybe 10W max each and ram I am unsure about but I know it is low, especially with DDR3 vs the older DDR2.
 

3Ball

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Thanks for the reply guys, and yes I am aware of where the main power draw come from, but the other parts of the system cannot be ignored in the overall picture, which is why I listed them.

Considering the power bill is a non issue in this regard, i'm still fairly certain of the video cards pulling 400w on their own plus the rest of the system.

This source shows the power consumption of the GTX260 in SLI: http://www.tomshardware.com/reviews/geforce-radeon-power,2122-6.html

This one shows the system with the GTX275 drawing more power the the GTX260 (as expected): http://www.tomshardware.com/reviews/geforce-gtx-275,2266-14.html

Throwing in the fact that they will both be OC'd I would wager them to be pulling slightly over 400w on their own. I am going to go with the TX950w until someone persuades me otherwise. I know this is one of those scenarios where it sounds like I have made up my mind and that it was pointless to make the thread, but its more along the lines of me trying to find a sensible reason to change my mind. Just dont want to steer my buddy the wrong way.

Best,

3Ball
 
What you linked was to global power consumption. ie, all parts included. It also says at AC source, so it is the draw of the PSU, not the draw of the system. The draw of the PSU will be higher and the PSU is rated for the draw of the system.
According to this: http://www.overclock3d.net/news/gpu_displays/gtx_280_gtx_260_final_specs_performance/1
The GTX 260 has a max draw of 182W, which will likely never be hit.
Also your first link just linked back to this thread.
And why would you change your mind considering they are the same price and the one you chose is better?
 

3Ball

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I edited the first link (thanks for pointing that out). I am aware of what the 2nd link showed, I merely referenced it to show that the GTX275 is pulling more power than the GTX260, since the first link doesn't show the GTX275 directly. Mainly just to verify what I am trying to say (don't want it to seem like I am pulling numbers from nowhere).

As far as changing my mind, I just wanted someone to agree with me that it was better. I didn't know if I was missing something. I found it odd that someone would consider the HX750w over the TX950w, that is why I made the thread...to see if anyone else shared that sentiment.

Best,

3Ball
 

Nope. You're definitely not missing anything. For the same price, that 950 will provide more power with the same quality :). The only ones who would get the 750 over it are those who care about power efficiency.
 

RickyT23

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Personally I dont think it matters too much, the Corsair PSU's are really good, and a 750 watt one will probably be able to handle 850 watts + continuous without having any problems. I read a review of my HX850 and it was tested stable at 1084 watts or something (!)
 
G

Guest

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You need to remember that the HX is modular,the TX isn't.That means that with the HX you can remove the cables you don't use.
 
things have changed

look how many Gold certified modular power supplies there are

http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=2010090058+1409743843+1131509966+1297819680&QksAutoSuggestion=&ShowDeactivatedMark=False&Configurator=&Subcategory=58&description=&Ntk=&CFG=&SpeTabStoreType=&srchInDesc=

even silver is nothing to sneeze at

http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=2010090058+1409743844+1297819680&QksAutoSuggestion=&ShowDeactivatedMark=False&Configurator=&Subcategory=58&description=&Ntk=&CFG=&SpeTabStoreType=&srchInDesc=