Is this PSU enough for this Graphics card?

[PFactorDave]

Question for those of you who know how these tech things work...  Will a PSU with the following specs properly power one of these  BFG - NVIDIA GeForce 9800 GT 1GB GDDR3 PCI Express?

450W Power Supply
Specifications
> ATX12V 2.2
> Dual 12V Rails
> PCI Express Ready
> Efficiency: > 80% Typical
> Silent 140mm Intake Fan
> 450W Peak Rated at 25°C
> BFG Thermal Control Technology
> Protection Circuitry
> MTBF: 80,000 Hours at 25° C
> Safety Approval: UL, CUL, TUV, CB
> Dimensions: 8.6cm W x 15cm H x 16cm D (3.4" W x 6" H x 6.25" D) 
> 3 Year Warranty

DC Output
> +3.3V = 22A
> +5V = 15A
> +3.3V +5V Max. Combined Wattage = 130W
> +12V1 = 18A
> +12V2 = 18A
> +12V Max. Combined Wattage = 304W
> -12V = 0.3A
> +5VSB = 2.5A

[gyrene81]

Sure, if that's the only thing plugged into that power supply...no mobo, drives, etc...and that's a BFG power supply as well?

Just for kicks...go with a 600 watt minimum...make sure it has at least 2 pcie and no less than 6 SATA connectors and go with a better brand...BFG started out as one of those Walmart econo brands and they make some decent stuff, but there is a limit.

[mipoikel]

450W is enough for that card + mobo + C2D + harddrives + everything....

[guncrasher]

I have that same ps never had problems running 8400 gt, but after getting new case and mb I had to replace it.  Makew sense to spend an extra 30 for a 600 w.   Cheaper in the long run.

Semp

[Skuzzy]

DC Output
> +3.3V = 22A
> +5V = 15A
> +3.3V +5V Max. Combined Wattage = 130W
> +12V1 = 18A
> +12V2 = 18A
> +12V Max. Combined Wattage = 304W
> -12V = 0.3A
> +5VSB = 2.5A

Let's take a look at those ratings for a moment.

The 3.3 and 5V lines are limited to 130W output, yet the combined total rating is 147.6W.  This means only one of the two can actually produce the maximum specified output.

Now let's look at the two 12V rails.  18A each?  Nope. If one hits 18A, the other can only do 7A as the combined output is limited to 304W (25.3A).  They could have rated both 12V rails at 24A, given the way they are cheesing the numbers as it is.

Marketing, aint it great?

[gyrene81]

450W is enough for that card + mobo + C2D + harddrives + everything....

Not really...look at the specs Skuzzy posted...he has the patience for that sort of thing.

[RTHolmes]

Not really...

how can you say that when you dont know what current the card + mobo + C2D + harddrives + everything are going to draw?

[PFactorDave]

Interesting...  As it happens, the PSU I listed is already in the computer.  I was hoping not to need to spend the money on a PSU upgrade.

[humble]

Adding to what skuzzy posted....

MTBF: 80,000 Hours at 25° C

This is an indication that all testing is done at 25C. This is a problem because normal operating temps are higher and all power supplies degrade in performance as the temp goes up...
http://www.pcpower.com/images/psmyths-chart.gif   

So at operating temps the unit will be at high load (assuming it can even initially meet the power demand). Since this is a large diameter top mounted fan its not a high performance gaming PS (100% will be 80mm rear mounted). While efficient at lower load this design breaks down quickly at loads of over 65% or so. Even if the PS can produce enough power, if you play games like AH that already generate both load and heat (since CPU and GPU are running at max) the PS will degrade further as heat builds further...increasing load till eventually something goes.

Do not purchase a power supply for a gaming rig that is not tested at 50C....period.

[PFactorDave]

Well...  It seems like I may as well explore upgrading both PSU and graphics card.  Any suggestions for how best to do both in the $200ish range?

What about these two?

http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=4494046&Sku=E145-0250

http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=3276567&Sku=ULT-LSP750

[Fulmar]

One simple equations solves most inquires on PSU label BS.

Volts x Amps = Watts

[RTHolmes]

BFG NVIDIA® GeForce® 9800 GT OC™ 1GB:
425W PCI Express®-compliant system power supply with a combined 12V current rating of 28A or more (Minimum system power requirement based on a PC configured with an Intel Core®2 Extreme X6800 processor)

they also do a non-OC'd lower power one:

BFG NVIDIA GeForce 9800 GT 1GB:
350W PCI Express®-compliant system power supply with a combined 12V current rating of 22A or more (Minimum system power requirement based on a PC configured with an Intel Core®2 Extreme X6800 processor)

If Speedfan can read your voltages, I'd chuck in the card, fire up Speedfan, chart the voltages, run the 3DMark06 suite a couple of times then check the chart. if the voltages are still within spec your good.

then again I dont mind pushing things a bit on my own machines, wouldnt risk it for a client though...

[humble]

I put this one in my wifes machine. I wouldn't put it in a "gaming rig" but it will run a single VC just fine if your running the machine at stock settings. It's tested at 40C not 50 but it will pump out solid clean power for a mainstream build judt fine. $40 after rebate
  http://www.newegg.com/Product/Product.aspx?Item=N82E16817341016     

This is the 9800GT on toms latest chart, seems like a good deal and exceptional performance for the $$$
http://www.newegg.com/Product/Product.aspx?Item=N82E16814130339&nm_mc=OTC-pr1c3grabb3r&cm_mmc=OTC-pr1c3grabb3r-_-Video+Cards-_-EVGA-_-14130339   

Looking at all the PS's in the 500-600W range this is another option...
http://www.newegg.com/Product/Product.aspx?Item=N82E16817341022 $45 after discount and rebate

Again I've got by Budget vs Bang viewpoint. In a "perfect world" you put in a 260GX and a PC power and cooling PS but the above should work just fine...

[gyrene81]

how can you say that when you dont know what current the card + mobo + C2D + harddrives + everything are going to draw?

Do I actually have to go there?


You seem to repeatedly miss the obvious so I'll point it out in red for you for the 9800GT:

350W PCI Express®-compliant system power supply with a combined 12V current rating of 22A or more (Minimum system power requirement based on a PC configured with an Intel Core®2 Extreme X6800 processor)

That doesn't include any other peripherals or memory.

He's looking for performance not BestBuy off the shelf boxed economy system. You should try one of the PSU calculators and see what the minimum specs truly are for a full system...then add 100 watts and make sure you're looking at the true specs of the PSU not the "marketing specs".

[mipoikel]

Have you ever measured how much your PC ACTUALLY needs power?

This capture is from finnish computer magazine tests:



http://www.mbnet.fi/nettijatkot/2008/10/virrankulutus/mittaukset.aspx (all in finnish )

Some months ago we did some measurements with Charge and we were really surprised of low consumption of our computers.