PSU question:

[thiduck]

I have a 800W psu(Zebronics , I know!!) and I am planing to change it.
Tell me this, if i purchase say a 600w psu, will it always consume 600w or if the mobo and dvd and hdd consume like only 400w, then will it only consume that much.
Asking for Electricity bill purpose.

 

[mcnumpty23]

it will only consume what it needs

 

[thiduck]

So, I have a 800w psu but my load is only as said 600w ,so I am consuming 600w only?? Just to be clear.(so no matter what you have, it is always better to have more powerful ones, for future proofing??)

 

[mcnumpty23]

So, I have a 800w psu but my load is only as said 600w ,so I am consuming 600w only??

yes basically--though theres also efficiency to take into account

though unless you have a really high end machine you wont use 600w

my psu has software that tells you how many watts you are using

at the moment its only drawing 100w

even when gaming it draws about 300w to 400w

assuming of course the software is accurate

future proofing is always a good idea

but a quality psu maker is also good--its not just about how many watts it has

 

[JamesSneed]

Yes PSU's just deliver power that is requested up to their max output so to speak. A 600w PSU used by an idle computer(say reading a web page) could be pulling less than 100w from the wall.

More power isnt always better, higher quality is what someone who builds their own should shoot for. Also most peoples computers even gaming PC's consume under 500 watts unless you run multiple graphics cards.

 

[groundrat]

No such thing as future proofing. I call it future resistant.

The big reason to keep your power supply a few hundred watts above what you actually need isn’t so much preparing to expand, but safeguarding your hardware.

The harder electronic components work, the quicker they wear out. With a power supply, this creates problems in that a failing power supply can feed motherboard errant voltages. Too much or too little voltage causes component wear and eventually fail.

So it is desirable to buy a power supply that is a little too large for your demand, because even under load, it will not be tasked enough to degrade it.

I’d also invest in an UPS, to keep your power supply safe.

Intel processors and motherboards take much less voltage to keep them happy.

 

[pit_1209]

A Psu don´t work that way, if you want to save money from your bill you got to get a 80 plus bronze PSU at least, that means that the efficiency of the PSu will be from 82% to 85%, that will depend on the load, most Psu works at maximun efficiency in 50-80% load.

A 600w PSu will consume the wattage that is currently delivering to your build + the efficiency difference. I mean let´s supposed yor build consume 400, so your PSu will consume 400+15% more if it´s 80 plus bronze a total of 460w.

Regarding power comsumption a 600-700w PSu will be plenty for any single gpu build if it´s from a good brand of course.

 

[geofelt]

So, I have a 800w psu but my load is only as said 600w ,so I am consuming 600w only?? Just to be clear.(so no matter what you have, it is always better to have more powerful ones, for future proofing??)

Not exactly.

True, a psu will conume only the wattage that is demanded of it, regardless of it's maximum capability.

Also true that overprovisioning has some benefits:
The psu fan will loaf and be quiet.
You will be prepared for some future upgrades, mainly in graphics cards which take the bulk of power demands.
But, realize that newer graphics cards are becoming more power efficient. Today, even a GTX690 only needs a 620W psu.

But some drawbacks:
A vastly stronger psu will be more expensive.
A PSU operates most efficiently in the middle third of it's range; that is ideally where you want to be.
A overly strong psu will come with more power leads that you can use, a cable management issue.

Whatever you do, buy only quality.
Here is one guide to psu quality:
http://www.eggxpert.com/forums/thread/323050.aspx

 

[JamesSneed]

Geofelt, hand t seen the eggxpert listing(saved that). The Tier 1 PSU list is a pretty good listing. All of the PSU's I recommend to others are on it. It does appear they used the same review sites I do as well, the ones that do actual real PSU testing and fail them when they don't live up. Thanks. Oh and OP this advise from geofelt is very good.

PS: I run a 550 watt PSU for my gaming rig 2500k oced and GTX 670. PSU fan rarely comes on even playing BF3. Im a weird one though since I like a near silent PC, while overclocking everything. PSU I chose is silent under normal even moderate loads and has almost no ripple on any lines(good for OC'ing).
http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story&reid=219

 

[thiduck]

A Psu don´t work that way, if you want to save money from your bill you got to get a 80 plus bronze PSU at least, that means that the efficiency of the PSu will be from 82% to 85%, that will depend on the load, most Psu works at maximun efficiency in 50-80% load.

A 600w PSu will consume the wattage that is currently delivering to your build + the efficiency difference. I mean let´s supposed yor build consume 400, so your PSu will consume 400+15% more if it´s 80 plus bronze a total of 460w.

Regarding power comsumption a 600-700w PSu will be plenty for any single gpu build if it´s from a good brand of course.

Ok, taking into a/c the efficient factor - It stil won't consume full power just because of its capability but consumes only what is required is what you are saying?(ofcourse + efficieny). (Like not just because it can, but only what is needed).

 

[thiduck]

How much does a tier one 600w cost anyway. Suggest a good psu for like 100-120$..

 

[geofelt]

How much does a tier one 600w cost anyway. Suggest a good psu for like 100-120$..

It would be hard to go wrong with one of the Seasonic X series psu's, the X650 is $129, but look for sales:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817151088
You are paying a premium for modular and gold rating.

I would have no worries about a tier 2 unit either. $100 should buy you one from Seasonic, Antec, PC P&C, XFX, or Corsair.

 

[thiduck]

Best answer selected by thiduck.

 

[JamesSneed]

Since you were being concerned about electricity usage here is a Platinum rated high quality PSU(not all Platinum rated PSU's are high quality). The Johny Guru tests shows this thing pulling 90% efficiency at 100% load which goes in the face of most people saying PSU's work best when not loaded very high.

The SeaSonic SS-660XP is a great PSU on sale for $129(well rebate) now as well:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817151121

http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story6&reid=326