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PSU 12v Rail?

Hey i recently setup a new gaming system and i am monitoring my psu rails and my 12v rail seems to be running at 11.6-11.7 v sometimes less when in game. Could this be a sign of not enough power on my 12v rails? new psu?

Thanks

Noc
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  1. The voltage is rarely exactly what it is supposed to be. You should be fine with that PSU, unless it has other problems.
  2. Well, under load it falls to 11.5/11.6 I assume that's normal
  3. It's normal for the voltages of the rails to vary and sometimes, they can vary pretty far from their rated voltage. That shouldn't cause any problems.
  4. TOO low is under 11.4V as that's out of tolerance for the ATX 2.x specification, but software monitoring is always a bit inaccurate.
  5. The PSU should shut down if it actually goes out of spec.
  6. i use an older system this a highend thermaltake PSU and get around the same and have not had any trouble until the rails started dropping below 11.3-4. that is when i would start seeing artifacts and the fans speed up and slow down slightly. so in my opinion the closer the 12 u can get the better but your voltages seem to be in the operable range. if you have a decent brand power supply like a corsair or seasonic i wouldn't fret to much as they have good consistent voltages. if ur running a cheap off brand power supply you might want to look at upgrading to a better brand in the near future. keep in mind that when your buying a PSU shoot for a wattage 30+% higher than you system requires. doing this a buying a good brand should stop this from happening in the future.

    newegg has a decent tool for showing what psu you will need but id still shoot for at least 20-30% higher for good measure.

    http://images10.newegg.com/BizIntell/tool/psucalc/index.html?name=Power-Supply-Wattage-Calculator
  7. xnocturnal said:
    Well, under load it falls to 11.5/11.6 I assume that's normal


    The ATX standard allows for a 5% voltage variation to meet "spec" .... you're at 4.2% with 11.5 which to my mind is rather HUGE. Your OC's are to a large part determined by voltage stability and 0.5 volt drop is, to my mind, far from stable. I look for units that can maintain no more than 1% voltage variation.

    Here for example you'll see some of the units I use frequently which maintains no more than 1% voltage variation (0.5 in the 2nd case) above / blow 12.00 volts

    http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story2&reid=142
    http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story2&reid=101
  8. rinval said:
    newegg has a decent tool for showing what psu you will need but id still shoot for at least 20-30% higher for good measure.

    http://images10.newegg.com/BizIntell/tool/psucalc/index.html?name=Power-Supply-Wattage-Calculator

    There's no need to put a 20-30% buffer zone into all the online calculator recommendations. They already put a buffer in there....GPU mfrs put a buffer in there, CPU mfrs put some buffer in there, all the mfrs put some buffer in their recommendations. Modern PCs consume significantly less power than most people think. A recent article on power consumption in three modern PCs: http://www.silentpcreview.com/article1245-page1.html
    Notice that a PC with an i5 2500K and an HD 6870 at full load running Prime95 and Furmark only consumed 237W!
  9. ^+1

    OP, buy a new power supply
  10. I'm pretty sure that the recommendation from Dell is because of the low voltage of your 12V rail. What is the make/model of your PSU?

    Edit: Changed instability to read low voltage on the 12V rail.
  11. ^ Yep, a .4v drop is more than I want to see, especially when it starts .3 below 12v
  12. So. Who is correct here? ...I've got a bunch of mixed answers
  13. xnocturnal said:
    So. Who is correct here? ...I've got a bunch of mixed answers


    Your PSU is on the edge of causing instability, but what is the brand and model of your PSU?
  14. Cool master 500watt Extreme Plus. Was pretty cheap.
  15. Best answer
    Rugger said:
    There's no need to put a 20-30% buffer zone into all the online calculator recommendations. They already put a buffer in there....GPU mfrs put a buffer in there, CPU mfrs put some buffer in there, all the mfrs put some buffer in their recommendations. Modern PCs consume significantly less power than most people think. A recent article on power consumption in three modern PCs: http://www.silentpcreview.com/article1245-page1.html
    Notice that a PC with an i5 2500K and an HD 6870 at full load running Prime95 and Furmark only consumed 237W!


    I agree that newegg gives a good ideal of exactly what you need to your specific build with exactly what you have in it and at the exact clocks your set to + about 20ish% overhead. but you need to keep in mind that unless you go with a HIGH end good name PSU with 80% bronze or better your PSU wattage can dip as high as 30+% from what the label states.. and the hotter it gets the more wattage you loose that is y i always throw the extra 20% over what newegg shows which gives me a good 40ish% cushion in case i upgrade or the psu overheats and drops wattage production. it also gives me a little room for overclocking without any major impact on the system.

    anyway back on topic if your voltage stays consistent where its at you might be ok but its ify. if its bouncing then you will want to upgrade PSUs to a higher wattage or better brand depending. keep in mind if your overclocking you want as stable voltage on your rails as possible as well as keeping it as close to 12 volt mark as possible to keep from running to issues. bouncing voltage on your rails = harder work for your VRM to maintain the proper voltage to your cpu. the more the CPU voltage bounces the more instability or performance degradation you will see.
  16. xnocturnal said:
    Cool master 500watt Extreme Plus. Was pretty cheap.


    Yep, there's your problem. It's new PSU time for you, I believe.
  17. Awesome. Okay thanks
  18. Best answer selected by xnocturnal.
  19. went with a 750watt ThermalTake TR2 RV, 80+ bronze. Thoughts?
  20. Not the brand that I'd go with, but it should at least be an improvement.
  21. Yeah its modular which is nice and I figured 80+ bronze was a steal with 750watts for 79.99
  22. Keep in mind that a lot of power supplies that seem cheap for their features are that cheap because that's all that they're worth. It's an improvement, but ThermalTake isn't nearly the best out there.
  23. Yes I'm sure ii can dish out another hundred dollars if it decides to take a turn
  24. my games some time crash and sometime pc shut off, i see bellow 11.3v under load, no OC here all is stock, my CX600M is dying i guess, should i get the EVGA 600B ?? ppol say its better more stable and has higher end Caps ??
  25. 600B is probably worse.
  26. A PSU won't shut off the voltages go out of spec. Under voltage protection will kick in far lower, usually when the voltage is at least double out of spec.

    If your computer is having zero problems, looking at some software voltage and changing your PSU is a poor idea. It can just raise a false alarm. It can help to compare the voltages to the BIOS readings for accuracy, but 11.6V and even 11.5V sounds normal for a cheap group regulated power supply under load. If you ask me, that voltage is exactly where it should be since computers crossload.
  27. in BIOS is 11.808v when i play games i have seen less than 1.35v, sometimes (most of the time) game just crash, and less times pc shut off, also i noticed that under load my PSU its quite hot, i touch it and im pretty sure its above 55° or 60° and this PSU has more than 2 years of use, first HD7850, then a GTX660 SSC EVGA, now a r9 280 dual+x OC 3GB and is when problems started, happens only with new titles wich im sure sucks more power than Warlords of Draenor or Crisys 2, never crash or shut off with this 2 titles :(
  28. oh so EVGA 600B its worse ? so a 700 or 750 unit from EVGA would do the trick ? i dont have many options here in cuba
  29. EVGA is all about which series , you want B2 , G2 , GS. are some of the better models made by reputable companies.
  30. so if i found any B2 i can go for it ? even 600W ? cause the other psu here available is the CX750M and i dont know if it is the same crap than the 600W model ?
  31. B2 doesn't come in 600w.
  32. ahh, good to know, then its start in 700W range ? and CX750M would be good to go with ??
  33. Agiel said:
    in BIOS is 11.808v when i play games i have seen less than 1.35v, sometimes (most of the time) game just crash, and less times pc shut off, also i noticed that under load my PSU its quite hot, i touch it and im pretty sure its above 55° or 60° and this PSU has more than 2 years of use, first HD7850, then a GTX660 SSC EVGA, now a r9 280 dual+x OC 3GB and is when problems started, happens only with new titles wich im sure sucks more power than Warlords of Draenor or Crisys 2, never crash or shut off with this 2 titles :(


    It's normal for PSUs with lower efficiency to get quite hot. You'll find that heatsinks are often attached to the casing which makes the casing of the power supply an extension of the heatsink; since the heatsinks hold the hottest components, if they are connected to the casing the casing, too, can get quite hot.
  34. this is not low efficiency, its not bad, 82% its 80 plus bronze ... if i conect it to 220V would it be more efficient ?
  35. Agiel said:
    this is not low efficiency, its not bad, 82% its 80 plus bronze ... if i conect it to 220V would it be more efficient ?


    Yep. But really, heat can't just magically appear. Heat is exactly what it is, wasted energy. Really, all the DC energy turns into heat inside the computer, and the difference of AC and DC is the heat formed inside the power supply. 82% is going to be peak efficiency, typical efficiency is probably going to be more in the 70s, and under high loads especially it should get hotter.
  36. what about using 220v ?
  37. Yeah 220V is more efficient. Not sure how you'll do that without changing countries. Don't even think about flipping that red switch.
  38. i have 110V and 220V here, this PSU is auto volt no red switch :) i just never used 220v on my pc
  39. its rated 90-230v
  40. Where do you live? Never heard of a country with both.
  41. Cuba, yes u can have both here, 100v its the standard, but u can ask the elect company to give u 220v and ofc u have to pay it
  42. The amount you pay for 220V will certainly outweight the efficiency gains. But if you already pay for it, why not I guess.
  43. so i will eat more power from a 220v wall than a 110v ? really ? i though it was all the way around ...
  44. No the input voltage has nothing to do with that. DC power is simply whatever your hardware demands.
  45. then why u say it outweight ?
  46. On 220V it is more efficient. DC power is the same. The AC however will be a bit lower than on 110V. This is because the current is lower on the primary side when it is 220V.

    220V is more efficient.
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