Sign in with
Sign up | Sign in
Your question

450 watt power supply? max graphics card - best choice?

Last response: in Graphics & Displays
Share
August 4, 2012 5:48:48 AM

Hi,

I just built a i3 desktop w/ a 450 watt powersupply and was wondering, what is the max graphics card that this power supply can support? Lets assume that there is no price limit? what would be the best card without bottle-necking? if you have a better card suggestion, but the psu does not support...what psu would you recommend as well?


here are my components;

GIGABYTE GV-R667D3-1GI Radeon HD 6670 1GB 128-bit DDR3 PCI Express 2.1 x16 HDCP Ready Video Card

Antec VP-450 450W ATX 12V v2.3 Power Supply

Foxconn H61AP LGA 1155 Intel H61 ATX Intel Motherboard

Intel Core i3-2105 Sandy Bridge 3.1GHz LGA 1155 65W Dual-Core Desktop Processor Intel HD Graphics 3000 BX80623I32105



Thanks for all the help
a b U Graphics card
a b ) Power supply
August 4, 2012 5:54:05 AM

thats a good psu, you can easily power up the hd7770 ghz edition, hd6850 and even a higher end hd7850 which requires only 22A on 12v rail while you have 36A.
a c 289 U Graphics card
a b ) Power supply
August 4, 2012 6:03:25 AM

I'd say HD 7850 is the best card you can get without upgrading anything and without any bottlenecks.
Related resources
a b U Graphics card
a b ) Power supply
August 4, 2012 6:19:30 AM

shamsmu said:
thats a good psu, you can easily power up the hd7770 ghz edition, hd6850 and even a higher end hd7850 which requires only 22A on 12v rail while you have 36A.


He only has 30A on the 12V rail. You have to look at the combined 12V rating(360W). The individual rails just have their limits listedwhich has nothing to do with how much total 12V power can be provided.

The 7850 is also only a ~11A card (130W) not a 22A card. He'd have no chance powering a 260W card on a 360W PSU.

since he's only got a 65W CPU though he might be able to get away with a 7850. probably the best choice
a b U Graphics card
a b ) Power supply
August 4, 2012 6:25:54 AM

unksol said:
He only has 30A on the 12V rail. You have to look at the combined 12V rating(360W). The individual rails just have their limits listedwhich has nothing to do with how much total 12V power can be provided.

The 7850 is also only a ~11A card (130W) not a 22A card. He'd have no chance powering a 260W card on a 360W PSU.

since he's only got a 65W CPU though he might be able to get away with a 7850. probably the best choice



yup I type faster than I think lololol
Anonymous
a c 117 U Graphics card
a b ) Power supply
August 4, 2012 6:34:59 AM

unksol said:
He only has 30A on the 12V rail. You have to look at the combined 12V rating(360W). The individual rails just have their limits listedwhich has nothing to do with how much total 12V power can be provided.

The 7850 is also only a ~11A card (130W) not a 22A card. He'd have no chance powering a 260W card on a 360W PSU.

since he's only got a 65W CPU though he might be able to get away with a 7850. probably the best choice

http://www.guru3d.com/article/amd-radeon-hd-7850-and-78...
Measured power consumption R7850
System Wattage with GPU in FULL Stress = 256W
Subjective obtained GPU power consumption = ~ 106 Watts

Measured power consumption R7870
System Wattage with GPU in FULL Stress = 274W
Subjective obtained GPU power consumption = ~ 127 Watts

either card will work as long as total wattage is under 360 (80% of 450) and the graphic card is not more than 172 watts (80% of the 18 amps on the SECOND 12 volt rail; the PSU has two 18 amp 12 volt rails)
August 4, 2012 11:22:16 AM

I'm not understanding power supplies. Can you explain? I thought the psu was rated for 450 watts? How does all this fit into the equation. You guys are throwing around 256 watts. That is the max wattage of the gpu under full stress? Also, you guys are figuring for chip as well? Can you recommend a better psu and a better gpu that would not bottle neck on this i3?
Anonymous
a c 117 U Graphics card
a b ) Power supply
August 4, 2012 5:22:38 PM

jdajjarapu said:
I'm not understanding power supplies. Can you explain? I thought the psu was rated for 450 watts? How does all this fit into the equation. You guys are throwing around 256 watts. That is the max wattage of the gpu under full stress? Also, you guys are figuring for chip as well? Can you recommend a better psu and a better gpu that would not bottle neck on this i3?

your PSU is fine. to give you the very short answer any graphics card that needs only one 6 pin power connection will work.
for better efficiency you want to keep the maximum system power (cpu, gpu, hard drives, RAM and chipset) under 80% of 450 watts (450*.8) which is 360 watts. with a combined amperage of 36 amps on the 12 volt rail (36*12) is 432 watts. again to allow for best efficiency keeping the max load under 80% that would be 345.6 watts. overestimating 150 watts for the system (cpu, chipset, RAM, fans) that leaves 195 watts for the GPU.
now that is the long winded version of any single 6 pin power connection is safe.

as far as bottle-necking; a gpu will not bottleneck a cpu; the game is what causes a load on the cpu more so than the gpu. for example playing single player BF3 will not affect the cpu and it will keep up with any graphics card. even a 7970 in BF3 will notget bottlenecked, it keeps up with a quadcore i5

playing multiplayer maps in BF3 or skyrim will substantially increase the cpu load and it will struggle in attempt to keep up taking a hit in FPS.


the best options for getting a graphics card that your PSU can handle is the 7850 or the 7870. now which one of those that will balance an i3 depends on the game you play. if you play cpu intensive games like skyrim or BF3 MP maps then the 7850 would be the better. if you play D3 or know you may upgrade to an i5 later then get the 7870. you have choices.
a c 236 U Graphics card
a c 126 ) Power supply
August 4, 2012 5:39:57 PM

One of the best cards around is the GTX670, at $400 or so.
It requires a psu with 30a and two 6 pin pci-e power connectors.
Most GTX670 cards will come with a molex to 6 pin adapter.
Here are the specs for a EVGA GTX670. http://www.evga.com/products/moreInfo.asp?pn=02G-P4-267... 600 Series Family&sw=
It says it needs a 500w psu, but I think your psu could do the job.
Cheap psu's will deliver 500w, but not on the +12v rails, where it is needed for most things, including the gpu.
A quality psu, like yours will deliver a combined 30a on the +12v rails.
Now, that might be pushing it some.

If you can wait a week or two, the GTX660 should arrive, and it looks to finally be some real competition to AMD in the $300 price range.
http://www.tweaktown.com/reviews/4869/nvidia_geforce_gt...
Or, a 500-600w quality psu is really not that expensive.

Here is a PC P&C silencer 500w unit with 38a that would do the job @$60 after rebate:
http://www.newegg.com/Product/Product.aspx?Item=N82E168...
August 4, 2012 9:26:59 PM

have been reading about the gtx 660...and can wait. do you think that only reference cards will be released, and later on manufacture specific cards that are modified will be released much later, or at the same time? If so, when is it supposed to be released? I read around aug 14-17th. What do you think the price point will be? 200-300? or lower, and if so, is it going to be better than an amd radeon hd 7870?
a b U Graphics card
a b ) Power supply
August 5, 2012 1:57:24 AM

yeah the gtx 660 ti seems to be worth the wait. Performance wise it is very close to the gtx 670 and its actually beating the hd7870 in all cases and even the hd7950 in most games. We are likely to see the reference models first and then the manufacturer specific models afterwards. (maybe a month or so)

http://www.tweaktown.com/articles/4873/nvidia_geforce_g...
August 5, 2012 8:44:37 PM

will i need to upgrade my psu for the gtx 660?
a c 289 U Graphics card
a b ) Power supply
August 5, 2012 8:57:44 PM

Nope!
a b U Graphics card
a b ) Power supply
August 6, 2012 2:17:08 AM

jdajjarapu said:
will i need to upgrade my psu for the gtx 660?


don't think so, since your psu is good enough to power up even the gtx 670.
August 6, 2012 2:58:15 AM

thanks....very good news to hear.
August 13, 2012 1:20:13 AM

was wondering...will my current psu have the right connectors to power the gtx 660? Also....what power supply would i need to power 2 gtx 660? appropriate connectors, correct watts, etc....? was thinking of building a new rig, and want to future proof by buying a motherboard with 2 pcie slots. would buy 1 gtx 660 now, and 1 down the road.
a b U Graphics card
a b ) Power supply
August 13, 2012 1:29:45 AM

a gtx 670 draws around 170w on max load. Since your antec 450w psu has 360w continuous flow on 12v rail, it may well be able to power up a gtx670- so in theory the gtx660 ti should be more power efficient and hence you should have no problem running it with your current psu.

this is all you need for a gtx 670/660ti sli.
http://www.newegg.com/Product/Product.aspx?Item=N82E168...
Anonymous
a c 117 U Graphics card
a b ) Power supply
August 13, 2012 1:55:25 AM

i'll do some guesstimation from what i known.
the gtx 660 uses one 6 pin PCI connection. it is doubtful it will need all 150 watts that can be supplied to it (75 from the PCI slot and 75 from the 6 pin power connection)

so i will guess the max load will be 140 watts. now that 450 watt PSU you are thinking of will cover that but to run a SLI set up lets play with some numbers:

140*2 is 280 watts and add 110 watts for the system for 390 watts needed on the 12 volt rail a quality PSU will provide 80% of its total wattage on the 12 volt rail so:

390/.8= 487.5 and to keep the max load no more than 80% 487.5/.8= 609.375 (lets round up to 610 watts)

you could get by with a 600 watt PSU but you'd be better off with one 610+ watts with 41+ amps on the 12 volt rail.
a c 236 U Graphics card
a c 126 ) Power supply
August 13, 2012 2:34:31 PM

jdajjarapu said:
was wondering...will my current psu have the right connectors to power the gtx 660? Also....what power supply would i need to power 2 gtx 660? appropriate connectors, correct watts, etc....? was thinking of building a new rig, and want to future proof by buying a motherboard with 2 pcie slots. would buy 1 gtx 660 now, and 1 down the road.

On the assumption that the GTX660 will need only one 6 pin pci-e power connector, your Antec 450w psu will be fine.

To run two such cards in slim you are looking at about 600w.
But... I don't think that plan is a great one.

If you want a graphics upgrade, it will be simpler to just sell the GTX660, and replace it with a single stronger card.
Yes, you may well still need a stronger psu. The Antec 450 can deliver 30a on the 12v rails. That should be enough to power even a GTX670. But, that will not be a great jump in capability.
Today, a stronger card would be a GTX690, which is very expensive. By the end of the year, we might well see a single stronger card positioned between the GTX680 and the GTX690.
Such an upgrade strategy would not require changing your motherboard to a more expensive sli capable motherboard.
It would also avoid any microstuttering issues.
Read this:http://www.tomshardware.com/reviews/radeon-geforce-stut...
!