Debate on PSU requirements of nvidia 8800 GT/GTS cards

By Mekaonija ยท 20 replies
Feb 14, 2008
  1. Moderators Note:
    This thread originally began as a part of One 8800 GT or two 8600 GT, eventually it turned into a discussion about PSUs, so in an effort to tidy things up I've copied the original thread to here and then deleted posts not pertaining to the PSU discussion from this thread. The other thread has most of the PSU discussion deleted and is only contained here now.


    Well my friend has told me he will be getting a new computer sometime soon so he thought that the idea of getting 2x 8600 GT in SLi would be the best preforming for under 300$ I told him that 1, 8800 GT would blow that away and It costs about the same or even less than the 2x 8600.

    He seems pretty keen on wanting the 2x 8600 GT's no matter what I tell him, from things like the 8800 will melt my computer or how much more expensive it is or how 2x 8600's in SLi will get better performance.

    Can anyone correct me if I'm wrong about this, or would someone care to shed some insight on this. I do look at computers a lot and love to build them and look at all the new stuff coming out and there specs and all that so I'm not really a noobie, I have been looking at each of those cards specifications and the 8800 seems like it would be much faster but I'm not very familiar with SLi so I'm not sure how much It would effect the performance. I don't want him to get ripped off because either way he will be paying 300$ for a video card(s).

    BTW he has about 800$ max for this new computer, I chose all this stuff out for him in the picture below, YES I KNOW INTEL IS "BETTER" even though its not always true... But I chose AMD because It is much cheaper and still preforms really good. You might be able to change my mind though If you can get an E6000+ Intel processor running at 2.5 GHZ without over clocking for the same price range as AMD.

    Thanks a lot!
  2. alisbin

    alisbin TS Rookie Posts: 93

    two 8600s will get better performance at super high resolution, but if your not planning on running things in the 2400 x1800 range, go for the 8800 gt.
    also, i'd recommend getting a 6-700W powersupply. i'm not an AMD expert but from what i've heard they use more power and modern vid cards need quite a bit too.
    lastly, are you getting a sound card? in my experience having a dedicated sound card (turtle beach montego is nice) makes for better sound
  3. alisbin

    alisbin TS Rookie Posts: 93

    gts 512 would be better sure, but if whif goes that direction he DEFFINATELY needs a really good 700w+ power supply, 8800GTS cards eat power like cheap candy.
    also make sure that the new case will be able to fit that monster...
    another thing, 8800 GTs arent hard to OC, so you might be able to get a non OCed GT for $50 or so less and OC it yourself if you choose (the $50 can mean more ram :) )
  4. Rage_3K_Moiz

    Rage_3K_Moiz Sith Lord Posts: 5,443   +38

    700W+? Get your facts straight mate, the 8800GTS would do fine with a good-quality 450W PSU like an Antec Earthwatts 430W or the Corsair 450VX, or even a 400W Enermax Liberty PSU.
  5. skitzo_zac

    skitzo_zac TechSpot Chancellor Posts: 418

    I am running a 8800GTS (the old 640mb version) on a 600W PSU at it all works fine.

    Also the new 512MB one thats on the newer G92 GPU right? And I would of thought that would use less power than mine as it got a die shrink yeah? So you dont need 700W for a 8800 GTS IMO.
  6. Rage_3K_Moiz

    Rage_3K_Moiz Sith Lord Posts: 5,443   +38

    Not at all. All the PSUs I've mentioned are more than capable of running all that stuff easily. It's where the power's available that counts more than the total power available. A 700W PSU with only 30-32A on the +12V rails combined is a useless investment IMO.
  7. alisbin

    alisbin TS Rookie Posts: 93

    there i agree with you rage, i was just saying that in my experience i've gotten more consistent high amps out of higher watt PSUs (good quality ones i mean). of course you need to make sure it has enough amps.
  8. kpo6969

    kpo6969 TS Maniac Posts: 710

    This is so true.
    For example:
    500w @ 34amps = $55
    A very good deal, but in that ballpark wattage I would pay more $ for something like this:
    550w @ 41amps = $99
    This is the one I will probably get when I upgrade again:
    610w @ 49amps = $119

    Quality + Price (good value) + Performance = a good psu, the heart of your system

    Rage said (I agree)
    "A 700W PSU with only 30-32A on the +12V rails combined is a useless investment IMO."

    This would be a good investment
    700w @ 50amps = $99
  9. Bigfellla

    Bigfellla TS Rookie Posts: 98

    LOL kpo wern't you flaming me a month ago for suggesting a 550W psu? My memory might be fading. It depends on what you run and how hard you push it (e.g. oc). I had a corsair 520W, but upgraded because i noticed 12V rail droop. I have money so i just got a 750W corsair, sweet psu, with 5 year warranty (60A on 12v). NOt needed of course, but peace of mind.

    The 8800GT will (as kpo correctly said) hammer any sli cards below it, especially if you oc.
  10. kpo6969

    kpo6969 TS Maniac Posts: 710

    To refresh your memory:
    post #43
    "All good points. I guess i am in the "i would rather be safe than sorry" camp."

    So what does recommending a 500w psu @ 34 amps for $55 have to do with your choice to upgrade from a 520w psu @ 40amps for $115, to a 750w psu @ 60amps for $150?
    Not everyone has extra $ to spend which in my opinion is not prudent.
    The EA500 unit is fine for a 8800GT and has excellent reviews. (reviewed yesterday btw)

    I stand behind my posts and have documentation to back up my facts.
    I wasn't flamming you previously but when called out, I do respond.
    No hard feelings
  11. Bigfellla

    Bigfellla TS Rookie Posts: 98

    What does it got to do with it you ask?

    1. In that same thread you said essentially "if you know what you're doing you can run it (8800GT) on a 250W PSU" (post 22)


    2. It will run fine on a 380W

    So which is it mate, a 550W, like i recommended and you flamed, or a 250W?

    just be consistent is all im saying. You argue for the point of arguing. Rage totally agreed that a 250W is "grossly underpowered". You just seem to find references for whatever point you are trying ot make at the time, to prove someone 'wrong' in your mind. The point of this forum (i gather) is to provide, consistent and solid advice.

    Now i have never advised anyone to use a 750W PSU (i got mine cheap and i like corsair), but i certainly did say a 550W.

    Now all of the sudden, you are going to upgrade to a "620W" PSU. Lol.

    So, what is it then? 250, 380, 500, 550, or 620? Essentially, my point is, your advice on this thread, is exactly the same advice i gave on the thread you quoted, and flamed.

    Get it straight mate, coz you sound confused.

    ps, the review quotes the psu at nearly $100 not $55, so if you were to spend 100 on that, i would get slightly more headroom with a 550W one. The corsair is good value. He never said he didn't have money, so why assume. If anyone wants more help on PSU's i suggest you look here:

    no hard feelings at all mate, really, i just respect a consistent approach, where we get your considered opinion, not everyone elses.
  12. SNGX1275

    SNGX1275 TS Forces Special Posts: 10,742   +422

    This thread is about to the point where it is going to get closed.

    kpo6969 was agreeing with Rage that alisbin was oversuggesting a PSU. Rage said that you could get by with a 400W Enermax Liberty. Which I'd agree with.

    Then you Bigfellla came in to this thread that really had gone off track anyway to take a shot at kpo6969.

    In the previous thread that you guys clashed kpo6969 politely countered a post of yours and your next post began with "LOL<OLOLOLOL". You had to take 1 line where he referenced another forum and used that to start a dispute.

    Then in that same thread when I said I'd break out a multimeter and a power usage meter and run it on my system which should pull more power than the guy in question's system you came back with "Yes. You can read."

    So it seems to me that you have the history of flaming people, not kpo6969.

    The entire argument has basically been you don't need a high wattage PSU to run an 8800, you need one with a 12V rail that can handle the card. The recommended for the 8800GTS 320 which should be using more power than the new GT or GTS is 26A on 12V PSU. That is for the entire system. Now the way electricity works, and you probably know this, is Volts * Amps = Watts. I think some people are reading 26A as what the card needs, thats not true. I can attest to this because 26A * 12V = 312Watts. My entire system with the old 320 GTS doesn't break 244W under heavy gaming.
  13. Bigfellla

    Bigfellla TS Rookie Posts: 98

    So are you saying a 250W would be fine.... regardless, as i mentioned months ago a 550W is imho the requirement for such a gpu. I understand ohms law mate, i have been an electronic engineer for years. The flaming business however is simply your opnion.

    now can we get back to helping people, rather than making rediculous suggestions such as a 250W psu is sufficient.
  14. SNGX1275

    SNGX1275 TS Forces Special Posts: 10,742   +422

    Nobody suggested a 250W is sufficient, and my 244W under load is just concidentally close to 250, and is in no way an endorsement from me to run a 250W PSU with that type of hardware.

    kpo6969 never suggested someone use a 250W PSU either, he merely provided an example of someone doing so on another forum. This seems to be the whole basis for you arguing with him, and now me.

    I'm questioning your electrical engineering knowledge then if you are STILL standing by your 550W minimum for such a card. If you really did understand Ohm's Law then you'd realize that recommending a 550W minimum is a poor statement because you are failing to address the critical part in this problem, which is the amperage down the 12V rail.
  15. Bigfellla

    Bigfellla TS Rookie Posts: 98

    I disagree. kpo, did suggest that "IF YOU KNOW WHAT YOU ARE DOING", a 250W psu would be sufficient. Go and read it again.

    Your question of my knowledge is not a concern of mine (plus electrical and electronic engineering is different), as i have said over and over, people come to this forum to seek advice, not conjecture, or baseless opinon. I made a 'tounge in cheek' joke in this thread re the fact that when i suggested a 500 or so watt PSU a month ago, i was flamed by kpo. Now he is suggesting 500 or so watt PSU's too, plus wishing to upgrade to a 620W PSU. See this within its context.

    Also, the critical part is not the amperage, becuase as you say, ohms law is a fixed relationship. So why then is your 244W quote important? Certain wattage, fixed voltage = amperage. Its more to do with the efficiency that the psu can deliver the rated specs. A $55 PSU is rubbish. A 250W PSU is rubbish. Simple as that.

    With respect SNG, what psu do you have?
  16. SNGX1275

    SNGX1275 TS Forces Special Posts: 10,742   +422

    The critical part IS the amperage. Sure its a fixed relationship, but a 550W PSU isn't just a 12V PSU, its doing many voltages, so the wattage per rail is varying. The important part for this entire debate is the amperage on the 12V, or if you insist on wattage then look at the wattage avaiable for the 12V rail.

    How awesome your 3.3V rail is matters little to none in this argument.

    Broad statements like a "$55 PSU is rubbish" aren't helping you convince me you are right and I'm wrong.

    Edit: $55 Not Rubbish PSU

    Here is what I'm saying about 12V Rail Amperage: 350W Enermax with a single 12V @ 26A which also happens to be $55.

    My 244W part was included to show you I am running an entire system using a max of 244W, so you don't need a 550W. Which was a lead in to my argument about amps on the 12V rail for the video cards being what mattered not wattages.

    My PSU is an Enermax Noisetaker II 485W.

    I understand your argument about efficiencies. While that is important, I'm still arguing for looking at the amperages on the rails then deducting 20% for an 80% PSU if you want to do it that way, rather than looking at it on a pure wattage viewpoint. The rails are whats important not the total system wide wattage.

    Provided another mod doesn't come close this, you'll likely have the last word for at least the next 8 hours, and probably 16. I'm heading off to St. Louis to watch a live taping of Diggnation.
  17. Bigfellla

    Bigfellla TS Rookie Posts: 98

    Where the hell did the 3.3V rail come in to this? Where did i say wattage is the only consideration?

    Im not saying you are wrong about your understanding of physics. Nor am i saying its all about wattage, to the contrary, i am saying its about efficiency. A $55 including postage, 500W or so is crap. The efficiency will determine the actual amount of power it can deliver, relative to the specs it claims. Most PSU's are rated at 25oC, how many psu's operate at 25oC? none. So the $55 PSU will not deliver the rated 500W, or probably 300W in summer under load, so, not worth a penny. Thats not even considering PFC, rail balancing, cross loading etc.

    I never said wattage is the key, efficiency is however, but, a 250W PSU< which is what he recommended, is never good enough as you agreed. What psu do you have?
  18. SNGX1275

    SNGX1275 TS Forces Special Posts: 10,742   +422

    Edits and crap screwed up the order. Normally I'm an advocate for edits, but they happened to fast. My post #16 should have all your questions answered. I've got to go or I'm going to get to StL too late.
  19. Bigfellla

    Bigfellla TS Rookie Posts: 98

    Have fun in St Louis mate. We will continue this when you get back if you want.
  20. SNGX1275

    SNGX1275 TS Forces Special Posts: 10,742   +422

    3.3V came into this because you've been advocating wattage so much I wanted to make sure that everyone understands that part of that 550W is being used up in that 3.3V, going back to my argument of amperage on the rails, not PSU wattage is the key. I linked above $55 PSUs that aren't crap.

    What you've said about efficiencies is right, which is why you don't buy a 2lb 600W PSU for $55. I wish more manufacturers would release single 12V rail systems again like PC Power & Cooling and that 350W Enermax I linked above. Seems like once this dual 12V rail started coming out PSU manufacturers saw this as a cheap way to keep the power stable and make people think 2 or 3 is better than 1. They should have focused on making one 12V rail and having it more powerful.
  21. kpo6969

    kpo6969 TS Maniac Posts: 710
    This is till the best bang for the buck psu @ $55 (currently) for anyone needing a 30+ amp psu (34amps)
    I did not mean to cause all this fuss but I hate to see people spend their $ when a better cost effective option is available that still provides the performance required
    Conclusion of review:
    Just for the record:
    The majority of this previous thread transpired before the review.was posted
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