4786645

PSU question

January 29th, 2009 04:00 AM

Ok, this will sound kinda noobish, i know. I'm planning to purchase a new Power Supply Unit in the near future, to replace my current 400W. My choise will most prolly be a 750W psu.
The qestion is: will it consume double the ammount of electricity even without heavy loadage? I think about those times when the PC is running idle. (without any games, psu stressing applications in the bckgrnd)

Basically, a PSU consumes its namely wattage, eg. 750W/hour in this case, or that's only the output performance?

4786694

Re: PSU question

January 29th, 2009 06:15 AM

It will only consume the power it needs, however PSUs are normally more efficient when running nearer their maximum load (it uses less power from the socket to provide the same amount of power to the PC, you lose less power in terms of heat, noise etc). So if you're worried about your electricity bill go for a smaller PSU output such as 500W-600W which will easily cater for any normal system. Some of the more efficient units are marked as 80plus (as in 80% efficient or higher) which gives you a guide.

If memory serves some of the best ones for efficiency are Antec's Signature series and some of the Seasonic range.

4786755

Re: PSU question

January 29th, 2009 08:18 AM

Hehe, yeah, i was a bit worried about the electricity bill it might could cause, but on the other hand, I don't intent to upgrade PSU for a good while once I purchased this new one. So keeping future's upgrades in mind (cpu, gfx card, mobo,ddr, etc...) i need to pick up a psu which will be able to deliver the juice needed to power up the next bulits aswell. That's why I selected the 750W of Corsair. (if i recall it correctly, it has 83-85% effinency) It should be enough even for crossfire/sli.

Thanks for the help!

4786787

Re: PSU question

January 29th, 2009 08:56 AM

You don't need 750W. I was running on 500W near enough 4 years ago, 3 systems later I'm still running on 500W (it's a different one granted, as the other machines are all 'in service' still), and with the possible exception of the dual-GPU cards (e.g. Radeon HD4870 X2) it will still take a more modern graphics card than my 8800GTS easily.

4787723

Re: PSU question

January 30th, 2009 10:26 AM

Well, then that's a true miracle what you've got I've a 400W currently, (it's not a the best brand, Codegen) and it cannot power up the rig if i install a soundblaster xtreme gamer audio card...And all i have are 2 hdds, 2 optical drivers, single core P4 cpu, and an x1650 agp vga in my built. So i'm unsure if +100W could handle a new built with all the main parts upgraded...But maybe +150W....To tell the truth, I was hesitating between 550W & 750W. Somewhere i read that a stronger psu can run PC more stable, this turned me to the 750...But maybe i should stick to the 550 and if it turnes out to be weak, i could re-sell it, and purchase a bigger one. All depends on the prices, i guess.

4787736

Re: PSU question

January 30th, 2009 10:46 AM

Whatever you do, don't get an off-brand PSU. You'd be much better off with a 550W ThermalTake than a 650W $20 no-name brand. They may be cheaper for more watts, but they don't often have the amps per rail that a lot of hardware requires.

A good 550W power supply will take you far, though. I have 550W powering a 2.2GHz dual-core Intel overclocked to 2.7, 4GB RAM, an overclocked 8800GT 512MB, two SATA hard drives, an optical drive, and two external USB hubs, and I've never had any power stability issues in the time I've had this build (over a year).

So, unless you're planning getting a dual-GPU graphics card (4870x2, GTX 295) or two regular graphics cards in SLI, and high-end quad core, 550W should be just fine.

4787745

Re: PSU question

January 30th, 2009 11:04 AM

Yeah, i know 20$ no-name psu won't worth it...I've heard Corsair is in the top5 brands, also it's in good price range, plus delivers enough amps on the required rails. The line 'all depends on the prices i guess' refers on the final decision between 550W and 750W of corsair.
Ty for the infos, your sys details give a good point for comparison and futher speculations for me..

4787889

Re: PSU question

January 30th, 2009 01:27 PM

FWIW, When I got the Antec NeoPower 550 that I have, our power bill dropped by about 50$ a month, parents were heaps happy about it.
Thats upgrading from a 250W MSI (some 70% BS PSU) to a 550W Antec 80%+

My next PSU is going to be a 1200W at 90%+, they are expensive but are likely to either keep the power bill where it is, or lessen it.

Now im running off a UPS which means less power is drawn from the socket

4788878

Re: PSU question

January 31st, 2009 08:11 AM

What does this mean in that particular case?
That's interesting, but totally reasonable that a psu with better efficiency reduces power bill...But with 50$ while doubling the wattage...This definitelly gives higher priority for the purchase of a new psu!

4788917

Re: PSU question

January 31st, 2009 08:59 AM

UPS stands for Uninterruptible Power Supply. It's a sort of external battery backup. You plug the UPS into the wall socket, and your computer into the UPS. It stores power in the event of a power failure, so your computer does not instantly shut down, giving you time to at least save all your data and power it down yourself. Better models have longer durations of reserve power, so you can carry on for a couple of hours without external power.