[dANGER boy]

So my Thermaltake Toughpower 775W power supply works great on my current system but I want to drop a better video card in it. However, not sure if 775W is enough.  This is what the system would look like after the upgrade.

AMD Phenom II Quad-core 965 @ 3.4 Ghz
16 GB DDR3 1600 Mhz RAM (4 sticks of 4GB)
ASUS M4A89GTD Pro motherboard
3 GB eVGA GeForce GTX 590
Basic DVD-RW
PCI-E Sound Blaster X-Fi Xtreme Audio

No overclocking so far on the CPU or GPU.

I heard somewhere that the new GTX 590 draws like 500W or something ridiculous so hence my doubts about the current power supply. Thoughts?

[zookeeper]

Wouldn't hurt to first check what something like this says. If it tells you that under full load you'd only need like 500W then surely you don't even need to think of upgrading.

[G0atmaster]

How's the amperage distributed?  Is it mostly on the 12 volt?

[newman]

According to this that card can peak at a whopping 491W. There really should be some sort of regulation preventing them from making cards that require a small fission reactor to run them.
The advice given here is good - check the linked PSU calculator. But honestly? I wouldn't buy that card, it's just too expensive and power hungry. I realize it's effectively the power of SLI on a single card, but ask yourself - do you really need that? A GTX 580 will run any game you throw at it great and it doesn't require nearly as much power. If future proofing is what you're after, consider the fact that the card's value will probably drop 50% in a year's time. I find that buying the latest, most expensive high end graphics card is almost never worth it.

[dANGER boy]

The calculation probably isn't 100% accurate but it comes in at 749W, 26W under what I'm supplying now.   Too close for comfort?

newman: I know, I know.  Right now I'm running the GTX 460 that I got for like $190 rather than buying the 500 series, but my education is paid for and I have a lot of money from working, so I really don't have anything better to spend it on.  I figure I could splurge once in my life on a video card, but I've by no means completely decided.  I might just wait until it's half the price it is now.

[newman]

In my experience whenever you get to a point where you can't decide what to spend your money on, it doesn't last long. I got really good at spending away my earnings over the years and managed to almost completely eliminate the "hmm what to spend this on" periods

As for the PSU being too close for comfort.. it depends on how you did your calculations. I like to give it at least 20-30% capacitor aging and put everything at full load to simulate the worst case scenario. In reality there probably won't be too many times when everything is working at full load (when playing newest games your GPU will be at full load but the CPU probably won't, etc - conversely if working in professional 3d apps etc your CPU will be strained but not the GPU).

I had a Corsair TX650W die on relatively recently, shortly after I installed a GTX480. In theory it should have been able to handle that card - but it didn't. I just counted my blessings that only the PSU died and bought the (much more expensive) Corsair 850W AX series, and that's been fine. Should actually be able to run SLI with that. Not sure how efficient Thermaltake PSUs are, though. If they're good enough, it should just be able to run that card. But in reality your current card can still run pretty much anything fine, so put your money in the bank or spend on something else. Graphics cards are best replaced when the old one has served it's useful cycle - your 460 gtx isn't anywhere near that yet.

If that money is burning a serious hole in your pocket, you might think about investing in more RAM, a good SSD (the ones with decent capacity are pretty expensive so they'll be very, very good at breaking your bank), a cool gaming aid (like sims? get a HOTAS stick. Or a racing wheel), or something else. Or blow it on gambling, booze, and women of questionable moral values.

[zookeeper]

I have a lot of money from working, so I really don't have anything better to spend it on.

Frankly, buying video cards which can do little but run computer games which are ultimately very pointless is one of the worst ways to spend extra money. I'm sure there's no need to give examples of better uses of surplus money.

[Nuke]

seems to me that computers have been using less power these days.

How's the amperage distributed?  Is it mostly on the 12 volt?

last 2 power supplies i owned had dedicated rails for both video card and cpu. no what will screw yea is when you use those 12v adapter cables and power the gpu right off of the same rails you power drives and fans off of. 775 is a lot, but considering how powerful that rig is (and how much everything likely costs), id do the safe thing and get a 1000w supply (it will likely be the last supply you ever buy). my next rig will aim for low power usage, low noise, and small form factor. want to get out of the high performance game while i still have my shirt.

I have a lot of money from working, so I really don't have anything better to spend it on.

Frankly, buying video cards which can do little but run computer games which are ultimately very pointless is one of the worst ways to spend extra money. I'm sure there's no need to give examples of better uses of surplus money.

id probibly spend it on booze, hookers, and/or dope. really giving me large sums of money is a bad idea.

[newman]

(it will likely be the last supply you ever buy).

I agree with pretty much everything you wrote except this. I just heard that statement way too many times. 2006, assembling a new rig: "that Enermax 500W may seem much but you'll probably be basing your computers on that same unit for the next 15 years". Or how about a few years later, "Corsair 650W? You'll never need more". Currently running my system off a Corsair 850W AX and I wouldn't be surprised if  I have to replace it by the time I upgrade to my next system.
Thing is, there's this constant myth being perpetuated that if you splash out for a super powerful PSU it will last you forever. Experience has taught me the exact opposite; PSU's internal components age and it's efficiency will drop with extended use. Eventually, it will fail, but with quality ones you'll probably replace it years before that happens, which brings me to my second reason why PSUs don't last you much longer than the other components; graphics card manufacturers keep coming up with reasons why you constantly need more. I'm fairly sure in a few years a 1000W PSU will probably be considered mid-range..

Fully agree on booze and hookers. Always a good investment.

[G0atmaster]

The thing is, a 775 watt power supply, even one with dual 12-volt rails, could still have the vast majority of the amps distributed along the 3-volt and 5-volt rails.  Back in the day, a 500 watt PSU that had 35 amps on the 12 volt was a good PSU.  That was in the GeForce 7800 era.  Non-dual 12-volts can actually be a good thing.  What a waste it would be if you had dual-18amp 12 volt rails, when your CPU used 10 amps but your GPU required 24 amps...

[Nuke]

meh, its late and power supplies have been the thing to give me the most frustration. you could always break out ohms law and do actual math. getting actual power ratings is an issue though, some psus will flat out lie to you on the sticker. they will give you the theoretical maximum instead of the practical value, or the tested value. its not like a mobo, i have brands i trust and those that i dont. same goes for memory. when it comes to psus there is no brand i can name off the top of my head that i would recommend. my 750w tough power works fine so far, i had a german made psu awhile back that was a piece of ****, cant remember the brand. so far my strategy has always been to go for overkill, figure how much juice you need and multiply by 4.

[dANGER boy]

I'll have to take a look and see how I have my powering set up.  The Thermaltake I have now has really high reviews for efficiency, delivery, and durability so I'm not too worried about it dying or anything.  I'll probably just save the money and wait to upgrade.  I have no clue what you guys mean by "rails" and "amps" (I know what an amp is but not when talking about PSUs in computers).

but considering how powerful that rig is (and how much everything likely costs)

Suprisingly, the systems specs you see at in the first post (but exchange that GTX 590 with what I have now, the GTX 460) only cost $1300...not that expensive if you include the 22" LED LCD HD monitor that I had to buy.  So long as you don't buy the most powerful stuff out there, you can build nice machine for relatively cheap.  Frys.com and Newegg.com 

[Nuke]

I'll have to take a look and see how I have my powering set up.  The Thermaltake I have now has really high reviews for efficiency, delivery, and durability so I'm not too worried about it dying or anything.  I'll probably just save the money and wait to upgrade.  I have no clue what you guys mean by "rails" and "amps" (I know what an amp is but not when talking about PSUs in computers).

rails are just another name for a power bus, usually with its own dedicated supply and regulation circuitry. devices are connected to it in parallel so that they all get the same voltage. each device will want to draw its own amount of current, and the total draw from the rails would be the sum of the current (measured in amps) of each device. so the sum of the current drawn by all the devices on the rail must stay below the rails nominal current rating most of the time and may go as high as the peak rating for short periods of time. exceeding peak current is bad, so you dont want to do that because thats where psu gets hot and devices start browning out. sometimes ratings will be in watts instead of amps, but thats just ampage multiplied by the rail voltage (w=v*a), so just divide watts by rail voltage to get current. pretty basic stuff.

now whats hard is identifying rails. a lot of psus just have a a huge bundle of wires coming out of a hole in the unit. you can get modular ones that have removable cables that make things a little more neat and makes it a little easier to identify rails. some rails may also pass to the mobo which will also draw current from them. you might get dedicated rails for cpu and video card if you got a good psu, but not always.

[Astronomiya]

Don't get the 590; get 2 Radeon 6970's and Crossfire them instead.  GTX 570 SLI is also about even performance-wise with the 590, and is cheaper than it is (or was at least a few months ago).  If you still want a single-slot dual GPU card, the Radeon 6990 offers better performance for the same money.

[JCDNWarrior]

I've been using a 750W Thermaltake power supply for around 3 years now, even with power hungry set ups. As long as you don't overdo your specs you won't require big huge power supplies.

I've never needed SLI or Crossfire, always went with the 'best medium class' graphics cards. For instance, I've been using the 8800 GT since it dropped price a lot, afterwards the 4870, now the GTX460. I'd advice to get the GTX460/560 or 570, or ATI's HD6770 or 5850. Graphics, and hardware in general, are not required to be the 'top of the line' especially today.

And if you know my works you know my custom built PCs can handle a lot

[newman]

I've been using a 750W Thermaltake power supply for around 3 years now, even with power hungry set ups. As long as you don't overdo your specs you won't require big huge power supplies.

I've never needed SLI or Crossfire, always went with the 'best medium class' graphics cards. For instance, I've been using the 8800 GT since it dropped price a lot, afterwards the 4870, now the GTX460. I'd advice to get the GTX460/560 or 570, or ATI's HD6770 or 5850. Graphics, and hardware in general, are not required to be the 'top of the line' especially today.

And if you know my works you know my custom built PCs can handle a lot

I would absolutely have to agree with this. Getting the most expensive top of the line gpu is almost never worth it in my book; they'll become obsolete around the same time as the much cheaper, 5% less performance runner-ups of the same generation. I find SLI/Crossfire totally not worth the hassle/price; nothing more than a marketing gimmick the GPU manufacturers came up with as a way for kids to lighten their parent's wallets.
I can understand wanting to splash out on something with a bit of extra quid burning a hole in your pocket, but surely you can find something to spend your hard earned cash on that you'll feel more of a benefit with in your every day life? With overpriced GPUs, you'll just stick them in your system, get arguably better performance, and forget they exist (ooh look Crysis 2 runs at 250 FPS, used to run at "only" 180.. who cares, really?).

[castor]

Thing is, there's this constant myth being perpetuated that if you splash out for a super powerful PSU it will last you forever. Experience has taught me the exact opposite

Same here. PSUs, hard drives, ram. That's what is going to fail, no matter what you buy. Never lost a cpu or a gpu (yeah, no overclocking here).

[Astronomiya]

I would absolutely have to agree with this. Getting the most expensive top of the line gpu is almost never worth it in my book; they'll become obsolete around the same time as the much cheaper, 5% less performance runner-ups of the same generation. I find SLI/Crossfire totally not worth the hassle/price; nothing more than a marketing gimmick the GPU manufacturers came up with as a way for kids to lighten their parent's wallets.
I can understand wanting to splash out on something with a bit of extra quid burning a hole in your pocket, but surely you can find something to spend your hard earned cash on that you'll feel more of a benefit with in your every day life? With overpriced GPUs, you'll just stick them in your system, get arguably better performance, and forget they exist (ooh look Crysis 2 runs at 250 FPS, used to run at "only" 180.. who cares, really?).

I would argue that it depends on what you want the computer to do; if you are a hardware enthusiast that likes to have the fastest machine available/just enjoys having a cool computer, they're totally worth it.  Likewise if you're a max settings whore like me (at least if you run a 30"/multi-monitors), especially if you want smooth 60 FPS for everything.  For everyone else though?  Yeah, probably not worth it, and I also recognize guys like me are really a niche market within a niche (people who would buy a high-end GPU in the first place).

SLI/Crossfire also usually aren't hassles at all; for the most part, it's drop the second card in, bridge them, install the profiles that come with the drivers, and away you go.

On the PSU front, as long the Thermaltake has sufficient amps on the 12 V rail (something which can be gleaned from the spec sheet), it should be sufficient for all but GTX 580 SLI.  Even 6970 Crossfire comes in at about 650 W or under for most systems, meaning a good 750 W is sufficient to run it without problems.

[dANGER boy]

Thanks for the input folks. I'll take a look at what amps are running through the rail and how I have the power all set up.

And for those people saying ATI....shame on you! Hardware may be good, but we all know that nVidia supports their drivers way better

[LHN91]

I've always had the opposite experience, actually. Every time I've had the misfortune to own an nVidia card, it's been a constant battle trying to find drivers that work properly. I've had times when I could get a game to work just fine, but the drivers messed up something as simple as a Windows Media Player visualization.