power supply purchase help

Discussion in 'PC Purchasing Help' started by eastmen, Jan 28, 2016.

  1. eastmen

    Legend Subscriber

    Joined:
    Mar 17, 2008
    Messages:
    9,983
    Likes Received:
    1,495
    Hey guys , my current power supply has hit 7 years. I want to buy a new one but don't know what wattage I should get.

    I currently run an intel i7 3770k with 16 gigs of ddr 3 2133 ram , 5 ssds , 1 bluray burner , a radeon 290 and a 1TB WD black drive.

    in the future I want to go dual gpu .

    I was looking at the Corsair RM850i But I am wondering if a RM 750i or do I go with a 1000 watt ?

    http://www.amazon.com/dp/B00YPNSQBS...olid=BTT4EYXK0APH&coliid=I1A70FFNIQFYYX&psc=1
     
  2. Rikimaru

    Veteran Newcomer

    Joined:
    Mar 18, 2015
    Messages:
    1,014
    Likes Received:
    395
    By a killowatt meter and measure current system at full load. Is CPU overclocked?
     
  3. eastmen

    Legend Subscriber

    Joined:
    Mar 17, 2008
    Messages:
    9,983
    Likes Received:
    1,495
    yea cpu is overclocked. I don't have the second gpu yet. I just want to give myself enough room for later this year.
     
  4. orangpelupa

    orangpelupa Elite Bug Hunter
    Legend Veteran

    Joined:
    Oct 14, 2008
    Messages:
    7,144
    Likes Received:
    1,295
    Can't you calculate it from the wattage specs?

    Like cpu is x watt. HDD 5v*amperage
     
  5. Rurouni

    Veteran

    Joined:
    Sep 30, 2008
    Messages:
    950
    Likes Received:
    216
    It is easier to read reviews from techreport or other site that measure system wattage and probably add 300w for dual GPU. Personally I think 750w is enough, but for dual GPU it will be on the edge. 850 should be enough. 1000 is more than enough.

    Edit: I just read techreport or review on 290x, the system with i7 3820 consumes around 340 under load. This is not the max load, more like real life scenario. Max load I guess would be around 400w. Throw in 300w more for the 2nd GPU and you get around 700w.
    Also GPU/CPU power consumption trend is decreasing, thus 850w should be safe.
     
    #5 Rurouni, Jan 28, 2016
    Last edited: Jan 28, 2016
  6. entity279

    Veteran Regular Subscriber

    Joined:
    May 12, 2008
    Messages:
    1,229
    Likes Received:
    422
    Location:
    Romania
    It's easier to use this : http://outervision.com/power-supply-calculator

    You will find that the total wattage needed is less than you would think. You may add a buffer, but IMO there's no need. Just make sure, beyond the wattage, that the PSU you are going to buy will have all the necessary connectrs
     
    tabs likes this.
  7. eastmen

    Legend Subscriber

    Joined:
    Mar 17, 2008
    Messages:
    9,983
    Likes Received:
    1,495
    Thanks for the link.

    So as it stands now I need 574 watts.

    Adding in the second video card and I need 835W

    So the 850 at $150 just makes it. The 1000w is only $180 however. So I might just spring for that since I will also be using a rift

    God I hope next gen cards use less power lol
     
  8. Rurouni

    Veteran

    Joined:
    Sep 30, 2008
    Messages:
    950
    Likes Received:
    216
    That link definitely assume that you use 100% of your power budget (with the exception of CPU where you can adjust it). You're likely to never touch that 835W. Of course if you have the money then 1000w is nice assuming that the 850 and 1000psu have the same quality.
     
  9. eastmen

    Legend Subscriber

    Joined:
    Mar 17, 2008
    Messages:
    9,983
    Likes Received:
    1,495
    the pricing is really close. I mean the 650 is $130 , 750 $120 , 850 $150 and the 1000 is $180
     
  10. Rurouni

    Veteran

    Joined:
    Sep 30, 2008
    Messages:
    950
    Likes Received:
    216
    That is what I usually do when I want to buy something a bit more than my initial budget allows.
    "hm, I need a new PSU. 650 is nice. But for a little more I can buy the 750w one. Might as well buy the 750w one... But wait a minute, might as well check the next tier... 850w for only $20 more? Sweeeet. But wait, since I'll be using it for a long time, maybe I should check the next tier once again. $30 more? That is expensive! Not so much difference from 850w though... Argh, screw it!" *buy the 1000w one*

    Actually I just did that late last year. My pc should run with a 400w PSU, but I ended up buying a 600w PSU after looking at 450, 500, and 550w price. A bit over the budget, but it's for the future!
     
  11. eastmen

    Legend Subscriber

    Joined:
    Mar 17, 2008
    Messages:
    9,983
    Likes Received:
    1,495
  12. ToTTenTranz

    Legend Veteran Subscriber

    Joined:
    Jul 7, 2008
    Messages:
    9,960
    Likes Received:
    4,553
    I have a system with a X79+4820K, 8x8GB DDR3, 2x290X, 4xSSDs,2xHDD and 2 different USB 2.0 sound cards (Xonar U7 for speakers, X-Fi Surround 5.1 for headphones).
    I power it all with the XFX 850W Core with no problems whatsoever.

    That power calculator says I should have a ~1000W unit, but the XFX's individual current ratings are actually within their recommended specs, and the unit can take a good overload towards ~970W anyways.

    But yeah I'd get that power supply if I could get it for $120 or even 120€. The cheapest I could get mine for was 125€.
     
  13. Blazkowicz

    Legend Veteran

    Joined:
    Dec 24, 2004
    Messages:
    5,607
    Likes Received:
    256
    I have a 350 Fortron (or FSP) since well, a long time. Reviewers loaded it up to 400W which is actually pretty high for a real PC.

    Haven't upgraded the PC very much but if I did there would be a chance that the power use goes down - though depending on hardware, peak power could go up, average power down.
    I really need a cigar lighter in there to put a bit of load on some times.

    There are tiny class-D amplifiers that run on 12V, one day I should piggyback on the PC's power supply?
     
    #13 Blazkowicz, Feb 6, 2016
    Last edited: Feb 6, 2016
  14. RedVi

    Regular

    Joined:
    Sep 12, 2010
    Messages:
    387
    Likes Received:
    39
    Location:
    Australia
    I have a similar system running on a Seasonic 660w platinum if that helps.

    Differences are; i5 4650k overclocked to 4.2Ghz, 290X, 3TB WD green, 2 SSD's.

    It has a hybrid fan that only ever turns on in summer when running a strenuous game or when running prime+furmark. So yeah, it's more than enough.

    Adding another video card would potentially be too much. But 750w Gold would cover it IMO, 850w would definitely leave enough headroom to maintain efficiency. I wouldn't bother with the 1000w unless you plan some crazy stuff. My last PSU was a huge 1000w corsair I bought in 2008, great but expensive for the time as I got sucked into the same staircase pricing. The 750w being out of stock didn't help. I feel like the $80 extra I spent would have been better kept. I went for efficiency and features this time around, extremely happy with my Seasonic.
     
  15. Grall

    Grall Invisible Member
    Legend

    Joined:
    Apr 14, 2002
    Messages:
    10,801
    Likes Received:
    2,172
    Location:
    La-la land
    Heya peeps, looking for new, shorter power supply. The 1100-something watt one I have is too damn long for the new case I'm thinking of buying to fit a new graphics card. It needs to be no more than 15cm in length to fit, ideally. Also, wattage 850 or more. Even 850 is overkill with just one GPU, but wear on PSU is less if you don't push it right up to the edge, also margins with voltage dips are greater, it runs cooler and more efficiently and so on.

    I really don't know PSUs very well. What brands are good? I've had Enermax and Corsair in my latest self-built PCs, that's 2 boxes over the span of 8+ years. My self-builts before that were back in the 1990s where PSU basically didn't matter. 250W was sufficient for anything/everything, pretty much. If you bought 300 or 400, you were a crazy overspending loon basically... :D

    Non-nostalgic nostalgia times:
    Back in the day, meaning around turn of the millennium-ish, I ran an AMD K6-3 300MHz overclocked with 83MHz bus speed, a peltier cooler sitting on top of it, 3 HDDs (one 7200RPM 3.5" drive, one 5200RPM 3.5" and a 4200RPM Quantum Bigfoot 5.25", ATI Rage 128 graphics card, Soundblaster Live sound card, 100mbit network card, Hauppauge TV card (which was shit with shit dynamic range btw), an assortment of fans including stacked 60mm YS tech fans on the Alpha CPU cooler plus a case-side 120mm by 38mm YS Tech fan, and once just for giggles, a full-height, 8-platter 5.25" SCSI server drive from the early 1990s that pulled 50-ish watts and even more than that on startup. Plus assortment of bus-powered USB devices. All of that on some noname 250W PSU.
     
  16. entity279

    Veteran Regular Subscriber

    Joined:
    May 12, 2008
    Messages:
    1,229
    Likes Received:
    422
    Location:
    Romania
    Please consult the mighty PSU review database ;) http://www.realhardtechx.com/index_archivos/PSUReviewDatabase.html (havent posted this link for a while here). I ussually go by Johnny Guru's reviews conclusions.
    Unfortunatelly, the physical dimensions of the PSUs are not listed in the tables there

    Each PSU entry has their OEM listed. Enermax e.g. no longer build their own PSUs , they usually commision CWT for it. CWT doesnt, IMO, build the best power supplies. Corsair usually employs either Seasonic or CWT as their OEM

    The top 2 OEMs are Seasonic & Super Flower (alphabetically). Sirtec & FSP are decent OEMs. Delta is usually highly praised for their build quality (donno how involved are in current gen PSUs though).. and so on
     
    digitalwanderer and Grall like this.
  17. RedVi

    Regular

    Joined:
    Sep 12, 2010
    Messages:
    387
    Likes Received:
    39
    Location:
    Australia
    Silverstone's strider Gold is a good PSU that is very short - only 150mm for the 850w and 750w models, 140mm if you can make do with 650w (IMO anyone who doesn't have highly overclocked extreme high end video card(s) can). They're not overly pricey, at least compared to Seasonic which also make great smaller PSU's. I have a few silverstone PSU's at work and my fiances ITX PC has had their SFX 650w gold psu for a couple of years with no issues.
     
    homerdog, digitalwanderer and Grall like this.
  18. homerdog

    homerdog donator of the year
    Legend Veteran Subscriber

    Joined:
    Jul 25, 2008
    Messages:
    6,153
    Likes Received:
    928
    Location:
    still camping with a mauler
    What are your specs dude?

    If you want small the Silverstone SST-ST45SF-V3 450W is a great deal. I have one in my mITX box powering an HD7950.

    For more power you can get the Corsair SF600 600W ($120) or even the Silverstone SST-SX800-LTI 800W if you're serious about that kind of wattage and can spend $200 on a power supply.

    Note that I'm not sure if the latter two PSUs come with or require a bracket to mount in a regular case. The SST-ST45SF-V3 definitely requires and comes with a bracket.
     
    #18 homerdog, Sep 20, 2017
    Last edited: Sep 20, 2017
    digitalwanderer likes this.
  19. Grall

    Grall Invisible Member
    Legend

    Joined:
    Apr 14, 2002
    Messages:
    10,801
    Likes Received:
    2,172
    Location:
    La-la land
    Haswell 4GHz, Corsair Dominator 16GB RAM, AMD R390X, WD Raptor HDDs x2, WD Green HDD x1, Corsair Neutron GTX SSD x1. +Bits and pieces, 5 case fans and whatnot.

    I don't need small form factor PSU; regular ATX is fine, just not longer than 15cm, that's all. :)
     
    digitalwanderer likes this.
  20. homerdog

    homerdog donator of the year
    Legend Veteran Subscriber

    Joined:
    Jul 25, 2008
    Messages:
    6,153
    Likes Received:
    928
    Location:
    still camping with a mauler
    In that case just get a SeaSonic SSR-650RM 650W. Even if you overclock your rig probably draws ~400-450W at its absolute peak (you will very rarely hit this). Even the SSR-550RM would be plenty but I understand you want some headroom. Don't worry about transient spikes, good power supplies are designed to handle them.

    There's no way you need 800+W for a single GPU system - even most mGPU rigs don't require that much. My rig is quite similar to yours (i7-3770K 4GHz, GTX970, 16GB DDR3, 2xSSDs, 2xHDDs, 2 optical drives and all the rest) and my SeaSonic S12II 520 Bronze 520W never breaks a sweat. Hell my 1000W UPS only reads ~20% load when playing BF1 :).
     
    #20 homerdog, Sep 20, 2017
    Last edited: Sep 20, 2017
Loading...

Share This Page

  • About Us

    Beyond3D has been around for over a decade and prides itself on being the best place on the web for in-depth, technically-driven discussion and analysis of 3D graphics hardware. If you love pixels and transistors, you've come to the right place!

    Beyond3D is proudly published by GPU Tools Ltd.
Loading...