Lost on new PSU to buy :( Please help

Hi guys/girls, i'm really stuck on what PSU to buy for my system, at the moment I need to get rid of my old piece of rubbish and get something quiet and efficient into my pc, please help if you can :)

Current rig:
Asus P5B deluxe L775
Core 2 Duo 6300
2GB 800mhz ram
Asus ATI HD 4870 1GB
No-name brand 500W PSU (old school though, has no 6-pin cables only 2 SATA cables)

Future rig plan:
Same motherboard
Quad Core 8200
4GB ram (800 or 1333)
Same gfx card
1xDVD writer
No extra bells and whistles (coolers etc)

I will only be running 2x7200rpm SATA's (160gb and 500gb) and dont plan on overclocking anything other than maybe the HD 4870. Possible other upgrades include moving to Crossfire with 2x 4870's (not a 4870X2). Im stuck as to how much power I will actually need, a similar thread spoke of powering a system much like my future rig with something like a Gigabyte ODIN 585w or a Corsair 550w. While the Corsair is lovely, its almost double the price of the Gigabyte here in South Africa :( so what other options can I look into (besides the ODIN)?

NB: Crossfire is a BIG maybe, by the time I can afford another 4870 I will probably also be able to afford a more powerful PSU (ie: with a full-time job :P), so this is mostly a PSU for single gpu use.

Please could someone provide me with some information, I will be eternally greatful and you will have gone a long way in helping a young man build a decent pc with his scraps of earnings from being a waiter/student :P

Thanks for any assistance provided.
10 answers Last reply
More about lost help
  1. The general rule of thumb is a high quality 500 to 550 watt power supply with sufficient current (amps) on the 12 volt rail(s) can easily power a system with any single video card made. A high quality 700 to 750 watt power supply with sufficient current (amps) on the 12 volt rail(s) can power a system with two video cards operating in dual mode. There are a few exceptions like the new ATI Radeon HD 5000 series cards which use less power due to their energy efficiency.

    A high quality 500 to 550 watt psu will have a +12 volt rail rated at 40 amps. A high quality 700 to 750 watt psu will have a +12 volt rail rated at 60 amps.

    In addition the power supply should be at least 80+ Bronze certified for energy efficiency.

    Corsair, PC Power & Cooling, and Seasonic are some of the brands that have a reputation for high quality power supplies that consistently earn high marks in technical reviews. They are reliable, stable, and come with a 5 year warranty. Some of the newer models come with a 7 year warranty. Lately we've been seeing a few other brands offering some high quality units. An example would be the Antec Earthwatts series which is an improvement over Antec’s older low budget Basiq models.
  2. Hahaha, just read that copypasta in another thread, useful but (like I said) Corsair is w2overpriced where I come from and PCP&C and SeaSonic follow that same cash route :(

    I don't want to be stuck with something like a coolermaster or huntkey though :P
  3. Do you have a local vendor with a web site? If we could take a look maybe we could find something for you.
  4. http://www.take2.co.za/list.php?type=4&cat=351&parent=92





    These are links to some sites I'm wiling to purchase from, although it does sounds a little overboard of me to ask everyone here to dig through them :/
    Price is, of course, a serious factor in this buying decision, as well as the obvious 12V rail ripple + overall noise levels. If the PSU is the heart of a PC then I need to stop using no-name crap :non:
  5. Please confirm - just one 4870 video card?

    Oficial ATI Radeon™ HD 4870 System Requirements

    PCI Express® based PC is required with one X16 lane graphics slot available on the motherboard

    500 watt or greater power supply with two 75 watt, 6-pin PCI Express® power connectors

    600 watt or greater power supply with four 75 watt, 6-pin PCI Express® power connectors for ATI CrossFireX™ technology in dual mode
  6. yup...
  7. "yup..."


    Yes, just one HD 4870 most likely :)
  8. Black-Lotus said:
    Hahaha, just read that copypasta in another thread, useful but (like I said) Corsair is w2overpriced where I come from and PCP&C and SeaSonic follow that same cash route :(

    The same question 6 - 8 times a day, so gotta excuse us if we take the ez route ....especially old farts like me with soon to be arthritic fingers :)

    I should have done that by now but Johnny is smarter than me !

    One mistake peeps make is just because a "vendor" (and I didn't say manufacturer on purpose) has a really good PSU, that doesn't mean all their PSU's are good. Like laptops 95+% of the time the brand name you see on the sticker is NOT the outfit that manufactured it. Which brands have their PSUs made by other companies? All but three that I know of.

    Seasonic and Fortron-Source / Sparkle manufacture all their own products. Enermax used to, but some of their products are now subcontracted out. Though Antec designs the PSU's for the most part, the Antec Signature (SG) series and CP Series for example are made by Delta Electronics.


    In past years, Antec used Channel-Well, but lately been using Seasonic, FSP and Enhance. Most PSU vendors follow a similar model w/ the different "quality tiers" being made by different vendors. You will sometimes see posts which say this company's OSU is great and this one sux and someone's out there laughing cause they were both made by the same outfit.

    Is PC power & Cooling a better outfit than OCZ ? Trick question....same outfit.

    Coolermaster often gets rapped here but the Coolermaster Silent Pro M700W is darn good PSU that is made by Enhance. So on that note, it would be hard to argue by brand alone that the Antec's made by Enhance are good and the CM units made by Enhance are "steenkie". CM has four different supply lines: Real Power, Silent Pro, iGreen, and eXtreme Power. The Silent Pro range to which the M700 belongs is their "top tier"

    Two good places to look for PSU ideas are www.silentpcreview.com and www.johnnyguru.com RThe first one takes a hard look at noise and temps whereas johnny's focus is primarily electrical.


    If you want the "best" look at the Editor's Choice models on the silentpcreview site, check the reviews and then head over to johnny's for another opinion. http://www.silentpcreview.com/Recommended_PSUs

    To my mind .... a mind shaped by reading both those sites, the top quality tier in the 650 - 850 watt sweet spot is held by the following:

    Antec Signature 650 and 850
    Enermax Modu82+ 625W
    Seasonic M12D 850W
    Antec CP-850

    That's right off the silentpcreview's editor's choice listing....johhny chips in his opinions accordingly

    The OCZ Evostream 600W is close to the same caliber, but can't match the ripple suppression or low noise level. Corsair? Nuh-uh... good luck finding one with this kind of ripple suppression. The SG-650 is pretty much in a league of its own here, and shows what can happen when you throw wads of cash at a renowned OEM known for server grade units and say, "Here, go nuts."

    But on the other hand, each of the units that were able to best the SG-850 marginally in one area were absolutely trounced by it in others. After a lengthy decision making process, I've at last settled on a score. This decision was not made lightly, because it is conceivable something else will come along that can take the crown away from this bad boy. But for now, the Antec SG-850 is the first and only unit to pull down a 10 in performance from me.

    If the CPX form factor catches on, the CP-850 will be flat out untouchable. It is completely unmatched by any ATX unit on the market I can think of. You'd have to spend twice as much as this thing costs to find the next best thing, performance wise.

    The Corsair HX series, at least the 850 is a match for the SG series electrically but it's a bit louder. But where the HX scores a 10 in performance from johhny, the TX drops to 8.5....that's what i was getting at when talking about individual units not being representative of a vendor's entire product line.

    Before closing off gotta say one thing. Just because an individual PSU is "better" doesn't mean you "need" it to be better.

    Taking one more quote off the silentpcreview site, "The CP-850's performance makes me ponder again whether the best PSUs, going back even a couple of years, aren't already much better than they need to be. Is there really any benefit to having 1% tolerance for the 12V line? Or 20mv ripple instead of 120mv?)"

    So sure that $229 PSU may be better than the $129 one but do you "need" it to be better ? The guy playing WoW w/ his friends would prolly say, no way. The guy trying for that 4.45 Ghz OC on his 920, would prolly say yes.

    As for sizing, most MoBo sites and GFX card sites have calculators and you can even download a couple but I find this one the most direct.


    BTW, if ya wanna test out your PSU under load, download OCCT and look at the graphs at the end of the OCCT 60 minute test run.

  9. Thanks for all the assistance :)
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