PSU advice

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venjhammet
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Hi everyone, I need help about PSU requirement. I will be buying my new rig and these will be the setup:

Corei5 2500K (will be overclocking)
Asus P8P67 Pro
2 x 2gb ddr3 1600 Corsair
Corsair A70 Cpu cooler
Inno3D or Palit GTX 570 (single card only)
2 x 1Tb Hdd

I was wondering if my old Silverstone ST60F-P 600W will be sufficient enough? I will be installing it on my old mid tower CoolerMaster CM690 II Plus with 8 x 120mm exhaust fan. I was planning on getting HEC Cougar 700w but I'm having second thought. Please I need some helpful advice. Thanks....

k1llg0r3
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600 watts should be sufficient for that build. If you ever plan to add more/upgrade then a bit more power would be recommended.

eire1274
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In truth, that rig only needs 400W, max. 600 is very safe.

There is a lot of misunderstanding on PSU voltages, now that high power units have become so affordable, and most custom builders go WAY over what is needed. You want to be higher in wattage than what is needed for future expansion, but going too far over means that you are literally wasting power.

Nick McDermott

massau
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Joined: 04/05/2010
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actually it isn't right what you are saaing you don't pull out the 1000watts if your pc isn't pulling them even if the power supply is rated to tha.
you will use more power because the psu has a lower efficantie at lower power usage but it has the same efficiency on higher power usage as the one of 600watts one so the only thing that counts is the efficiency of the psu. but it needs to be the most efficiency at your highest consumption.
and i would really say go for 600wats or a little bit higher, especially whne you want to overclock or upgrade your pc.

TheRealMan
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DO NOT get HEC, they are crap, it boils down to the quality of the PSU's internal components. if you get a junk psu and stress it to its rated wattage, it will fry, where as if you buy a "Kickass" psu, it will be able to handle the stress load that you are putting it under without the problem of voltage drop or spikes.

Almost forgot, its a smart idea to order a PSU with "PFC".

-TRM

GIGABYTE-X38-DS4 water cooled chipset - GTX 460 - Seagate 32MB(c) 500GB + Intel 120Gb SSD -- C2Q Q6600 3.4Ghz-8GB(4X2GB)- Thermaltake Toughpower 700W - Win 7 64-Bit Ultimate - CM-690
--Laptop T5850 C2D-750GB Seagate Momentous XT - 6GB 1X4/1X2 DDR2
--Server C2Q [email protected]- 4GB 2x2 - ATi 4850 Upgraded cooler - Seasonic 500 Modular - 2X 1.5TB WD/green 1X 320WD 1X2TB WD/black

ihatenvidia
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Joined: 04/01/2010
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Just get 700 to be safe, once you have a pc its easy to be tempted to do an upgrade, the price difference won't bother you anyway, and yeah don't buy HEC, those are not as good as other top brands, if you want sure quality go for corsair, silverstone or seasonic, if its too expensive there are cheaper brands like cooler master, thermaltake or xfx, although those first three I mentioned are better.

lali
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I remember buying a xpower780 psu from HEC...it failed after a week of making whining noises. I recommend brands like XFX, OCZ, or Corsair (which I personally have right now...TX750W). I learned the hard way to not buy a cheapo PSU. 700W is excessive and it can lead to less efficiency because it is drawing less power than it was designed to handle at a constant load.

Gentlemen.

ihatenvidia
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lali wrote:I remember buying a xpower780 psu from HEC...it failed after a week of making whining noises. I recommend brands like XFX, OCZ, or Corsair (which I personally have right now...TX750W). I learned the hard way to not buy a cheapo PSU. 700W is excessive and it can lead to less efficiency because it is drawing less power than it was designed to handle at a constant load.
lali wrote:I remember buying a xpower780 psu from HEC...it failed after a week of making whining noises. I recommend brands like XFX, OCZ, or Corsair (which I personally have right now...TX750W). I learned the hard way to not buy a cheapo PSU. 700W is excessive and it can lead to less efficiency because it is drawing less power than it was designed to handle at a constant load.
lali wrote:I remember buying a xpower780 psu from HEC...it failed after a week of making whining noises. I recommend brands like XFX, OCZ, or Corsair (which I personally have right now...TX750W). I learned the hard way to not buy a cheapo PSU. 700W is excessive and it can lead to less efficiency because it is drawing less power than it was designed to handle at a constant load.

How can an excessive power supply draw less power? Will you explain it to us. When it comes to psu it doesn't hurt too have extra wattage, there's a saying "better to have it and not need it than to need it and not have it", in fact most tech guys will advice you to have 20-30% extra wattage for your pc specs in case of future upgrade or hardware peak load. It doesn't matter if your psu is 500w or 1500w if your pc needs 400w it will give you 400w, those extra watts are there to make sure your pc get enough power on 100% load and in case you need to add more hardware, that's all there is to it.

eire1274
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ihatenvidia wrote:How can an excessive power supply draw less power? Will you explain it to us.

Okay, first off, remember that I normally build business grade machines, workstations and servers, and I follow the rules of long life. This is where the info comes from.

On a "heavy" PSU, one that is over-powered for the system that it is powering, one has to remember that a system that is designed to put out 400W will always be producing a total AC to DC conversion output of 400W, typically with a 25% "peak load" surplus (tends to be the average), meaning the PSU monitors draw and can "overclock" itself to produce an extra 100W in case of a sudden power demand increase (e.g. multi-drive disk spinup); however if this power supply is asked to produce 500W continuously on an overloaded system, it will burn out in a short period of time.

Now, on the underloaded side of things, if this same 400W machine is powering a 350W demand, that extra 50W is still being produced, and the extra is being recycled back into the AC/DC converter. The low wattage (or more accurately the amperage) recycled is under the stress limit (100W, which is what the system is designed to handle, see above on overloading) and will only produce additional heat. Now imagine that we have a 700W PSU on the same 350W demand, and we suddenly have a 350W surplus. That's double what the PSU is designed to handle as a stress (700W*¼=175W), and you will see the AC/DC converter fail or the system otherwise burn out due to voltage fluctuation or heat output.

Now, some PSUs offer EMI (electromagnetic interference) controls or PFC (power factor correction) that will better handle voltage and amperage outputs, and tend to be tougher overall because of these controls. Furthermore, PSUs with multiple 12V and 5V banks or channels actually have independent converters for each bank and flowback is handled in smaller amounts across the board because it is split up. I will ALWAYS recommend a PFC equipped multi-bank PSU within the 25% load limit of the machine, and my clients have always thanked me for systems that far outlive their warrantied period of life.

For instance, my video rig: micro-ATX AM2+, AMD Athlon X2 Brisbane 3.5Ghz (oc'd from 3.1Ghz), 2x2Gb DDR2 1066, 2x500Gb 7200Rpm SATA, PATA DVD-ROM, PATA DVD-RAM, HIS HD x4670 (oc'd). Total system draw, 430W. PSU is an OCZ ModStream 520W multi-bank EMI, which just passed it's 5th birthday.

Just remember that the power supply will always produce what it is rated to, and that overload can often be just as destructive as buying a weak PSU. Calculate your PSU requirements here (this is basic but will calculate the 25% for you): http://educations.newegg.com/tool/psucalc/index.html

Build for long life and you will see far fewer component crashes, and therefore less chances of blowing all of your digital life away!

Nick McDermott

ihatenvidia
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From what I've seen the worst thing that can happen to an overpowered psu is run inefficiently but in no way it can destroy the system, I have seen a lot of people build their pc's using psu with lots of wattage to spare and I haven't seen one that burned because of it, actually its quite the opposite for me I have seen too much of people getting their psu fried because of insufficient wattage. Back in the p4 era I used to replace a lot of psu for people because they were still using 300w and the dual core just came out and graphic cards are getting more and more powerful. I have seen the thermaltake tough power 1200w and corsair hx1000w be used on a single card setup in a lot of gaming forums and it didn't have any problems, in fact most pc enthusiasts nowadays invests in higher wattage psu (of course a bit more but not retarded like buying 1200w for an i3 setup) for future proofing and I haven't seen any of them have trouble with it aside from the usual psu being doa or defective. The op's build is a little high end, I don't think an extra 100w will hurt his system in case for a future upgrade the he might do like let's say change or add a graphic card, add more drives and maybe a water cooling setup, lets also not forget the OC factor here, I think his setup alone can reach up to 500w max load. Thanks for the input btw. i hope Rodney can join on discussions like these.

eire1274
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One must remember that with electronics, going over is just as bad as going under. With the thousands of machines I have replaced burned PSUs on, I know I'm operating on more than just supposition.

Never said it would destroy the system, but a PSU generating tons of unused power can kill itself over time due to accelerated parts wear.

And to say "If you overclock, you may hit 500W, so ditch your 600W PSU" just makes no sense to me. Why spend money for a bigger PSU if the existent part still has a surplus?

Nick McDermott

ihatenvidia
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Why did I recommend 700 watts? There's a couple of reasons, first is higher end models from certain brands starts with 650w to 700w, if there's no 600 should you get an inferior model if you can just get the 650 one?

Second is he didn't say if he is looking to upgrade in the future or not. The minimum recommended wattage of gtx 570 is 550watts disregarding whatever parts you might put in your pc and some tech actually advises to make it to 600, really, how harmful is a hundred watts more just in case you need it? I didn't tell him to buy an 800w or 1000w.

Third, that 100watts is the difference between being able to upgrade to an amd 6990/gtx 590 and not being able to.

Fourth, I'm using an i7 950 setup with an old 9600GT I borrowed, my total power usage is what? around 300+ watts? maybe less? I'm using a Corsair TX850 watts and it doesn't generate that surplus power and additional heat that you're talking about, my psu runs very cool and it doesn't experience any power fluctuation, even my electric bill isn't so different from my last dual core w/400 watts psu setup. The same goes with a buddy of mine who has an ocz 750w and only runs an i5 760 with a 6870, hell even Rodney builds computers with lots of extra wattage to spare.

Fifth, I don't read the last portion of the messages because most of it are signatures, he said that he already has a silverstone 600w, I didn't see it, so I will say that just stick with it, that is a good psu and he doesn't need to buy a new one, but if he does he doesn't need to be scared to get a higher wattage one.

venjhammet
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Joined: 05/22/2011
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Thanks for the advice guys very much appreciated. I have my system now:

Corei5 2500k
Noctua NH-U9B SE2
MSI P67A-GD65
4gb G.Skill RipJaws-X 1600 CL9
MSI N570Gtx Twin Frozr III

And I've tested it on my Silverstone 600W. Everything looks great and amazing but I haven't overclock yet cause I decided to buy the Corsair TX750W. As soon as I have it I'll do some overclocking. Thanks again!!!

venjhammet
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Joined: 05/22/2011
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I also read a few reviews about Hec cougar. It has low amphere only 30 and not an ideal psu. The GTX570 needs atleast 38. My silverstone has 42 which I think is safe but I opted for a much higher value so I grab the Corsair TX750W which has 60 amphere on the 12v rail besides I'm not going into SLi.

venjhammet
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Joined: 05/22/2011
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Yes I agree with you, never go cheap on a PSU or you'll end up a broken PC.