PSU for GTX 750 Ti

[GreiverBlade]

Edition: extra power hungry. "Thermi" was really funny, I can't get that 590 out of my head that smoked under light OC.

Pshhhh my Matrix did hit 995 core in SLI (+ a 4.2ghz i7-920) on that 700w

Thermi was valide for the 4XX series (specially the 480 "barbecue edition") only a EVGA 460 SC (who clocked like a FTW ) and a Zotac 480 AMP! For me in that series.

 

[Kanan]

Ah so then it's matrix semi-ghz edition.

Actually I like those my father still powers a pny xlr8 gtx570.

 

[Raminlich]

(We get more questions about GTX 750's and PSU's. Ironic, no?)
If that is a decent PSU, it should work. Of the (advertised) 195 watts on the 12 volt rails, the CPU uses (up to) 54 watts. With all of the other items in the computer, I'd think that more than half of that 195 watts is available for a GPU. And GTX 750's only use about 60 watts.
OP, are you using a GPU now, or just the iGPU?

wow i wasn't here for a little time so much massages has come , nice community.
thanks to you thebluebumblebee you have reminded me somthing that i think its important to discuss about my psu here.
Now my current gpu is Gigabyte GT 630 2 GB DDR3 , its been long time i using this gpu and psu and i have no problem.
i also tested a Asus GT 740 for a few days i had no problem with it too.
GT 630 power consumption is 65 and 740 is 64.
and some fellas says 740 need more power than 750? is it true?
so now some people says is enough some say not enough some test i had was ok, websites says other thing.
im saying this because im soo tight on budget.
im little confused here.

 

[Jetster]

To summarize; use your current PSU at your own risk.

 

[Raminlich]

Also Nvidia recommend 400w psu for GT 740
and on that a few days i had 740 i think i used most power of cpu and gpu, i was running 20 fps Fallout 4 on ultra quality and 1600*900 reso and i got no failure and everything was fine.

 

[okidna]

Judging by the UL code the PSU's OEM is Topower. Some of old Tagan units also use this OEM.

I used to have Tagan 2Force 430W, also built by Topower, it died spectacularly with a bang and smoke after 6 years of use because of the main caps gave up (leaking). I remember it started to show looser voltage regulation, higher operation temperature, and louder fan after I upgraded to a new hardwares which need more power from +12v (AM2+ platform, GPU with PCI-E power connector, a couple of SATA HDD, new case with extra 120mm fans).

You might be fine running your system even with a 750Ti, but if I were you, just to be safe and for a peace of mind, I will buy a better PSU.

 

[Kanan]

It's kind of a action movie risk decision, do it or not, jump or don't jump. Hahaha... if you're so tight on money I guess the answer is simple, try the old psu first.

 

[Bill_Bright]

I'm not sure it's wonky just because it lacks 80+. 80+ isn't really relevant on low power psus.

I agree with the first sentence, not the second.

80+ certification does not guarantee quality. All it guarantees is a relatively "flat" efficiency curve across a full range of expected loads. Note that PSU makers have to pay Plug Load Solutions to have their PSUs tested for certifications. That does NOT suggest any real improprieties, or the appearance of improprieties of paying for the logo. Whether a PSU passes the certification or not depends only on the merits of the PSU (if it passes testing or not).

But a PSU can have phenomenal efficiency and not be 80+ Certified if the PSU maker did not submit the supply for testing. It would be a bad marketing move, but it can happen.

The issue is, consumers look for that 80+ certification. And we, as advisers, tell people to look for that logo and PSU makers know that. So it is generally safe to assume if a PSU is not 80+ certified that it has lousy efficiency to start (typically ≤70%) and that 70% peak efficiency occurs at only 1 or 2 points along the load range (a bell shaped curve, not flat).

That said, it does indeed, generally speaking, take a better design and tighter tolerance components to achieve a "flat" efficiency curve in a PSU. This is because in electronics, PSUs are inherently inefficient devices. This is not a problem for other electronics that present the same load all the time. The product designers just match a supply to the 1 expected load for the best efficiency. But computer loads vary widely from near no load to maximum loads - so a supply with a flat efficiency is more desirable. Because it takes a better design and better parts, you can assume a better chance of getting a more reliable PSU if it is 80+ certified. Of course a "better chance" is not a guarantee.

And I disagree that 80+ does not matter on low power PSUs. It matters on all computer PSUs. I think it important to note that if a computer (motherboard, CPU, GPU, RAM, Drives, fans) needs 200W of power, it will draw from the PSU 200W, regardless if the PSU is a 250W PSU, or a 1000W PSU.

The difference comes at the wall. The PSU will draw from the wall 200W, plus whatever it takes to compensate for the PSU's inefficiencies. An inefficient 70% PSU will pull 260W from the wall. That extra 60W is totally wasted in the form of heat. An efficient 90% PSU will pull just 220W from the wall. And again, it does not matter if a 250W PSU or 1000W PSU. So not only is there 40W less power being consumed, but there is less heat being pumped into the room the facility air conditioners must remove.

So it is all about the load, and the PSU efficiency, not the size of the PSU that matters (as long as the PSU is large enough).

 

[Frag_Maniac]

Keep in mind that 400w is a conservative estimate, go by 20 amps. They always error on the side of PSUs that don't put out as much amperage for their wattage as others do. Your PSU has two 12 amp rails, which when combined is a lesser amount than 24. How much lesser depends on the quality of the unit.

So the rule of thumb is, if it's not a well known quality brand, you want at least as much wattage as specified to make sure you have enough amperage. I would say what you have is a bit of a gamble, especially long term with heavy gaming. It's not good to go cheap as possible on PSUs. It's a very important part that if inadequate or fails, can take down other parts.

 

[Bill_Bright]

Keep in mind that 400w is a conservative estimate, go by 20 amps. They always error on the side of PSUs that don't put out as much amperage for their wattage as others do. Your PSU has two 12 amp rails, which when combined is a lesser amount than 24. How much lesser depends on the quality of the unit.

Sorry, but I think for some, this may make it more confusing - especially if confused to begin with (perhaps due to language barriers, of just a lack of experience in this area).

So to clarify, a "conservative" estimate, in this context, means in moderation, that is less generous or lower than may actually be needed.

Not sure who "they" are when you say "they always error", but the fact of the matter is, card makers and calculators always "pad" the results, or provide a more liberal or "generous estimate" - that is, they suggest or err on a "larger" PSU than users typically need. And that makes sense. They sure don't want you buying an underpowered PSU that won't work at all. It is ALWAYS better to buy too much power than not enough as the computer will still run just fine.

But note card makers always pad the estimate to a greater extent than calculators because they have no clue what CPU, number of drives, number of RAM sticks, etc. you have installed. A good calculator, like the eXtreme OuterVision PSU Calculator allows you to select the actual CPU, number and type of drives, number and size fans, number and size RAM sticks, and more to calculate the correct size PSU. This calculator even allows the user to factor in things like capacitor aging, CPU utilization and more. This calc stands apart from all the other PSU calculators because they have a full time staff of researchers doing the homework for us determining the power needs of 100s of different graphics cards, over 3000 CPUs!!!! and more.

Bottom line, there is no guessing with the eXtreme OuterVision Power Supply Calculator, no arbitrary numbers pulled out of thin air. This calculator is for newbies and pros alike - at least if you want to be thorough. Note it tells you your power needs, then pads the results by suggesting one a little larger than you need. And it even suggests a UPS size.

*****

The problem with 2 x 12A rails is the full 24A is not available to whatever may be connected to one rail. So if your graphics card needs 18A as an example, even though the total wattage of the supply may (on paper anyway) suggest there is plenty of amperage, there is not because it has been divided.

And sorry, but how much less when combined has nothing to do with the "quality" of the unit. And to that, they are separate rails by design so not sure where this "combining" of rails would take place. Or why. That said, there are some advanced "intelligent" multi-rail designs that do allow for current redistribution, but how that is done and the resulting "combined" current when done is set by design, not by quality.