Graphic Cards Help decide a PSU

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neomustdie

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hi, me buying a new Gfx card next week.... either the 8800 GTS 320 mb or 640 mb. Also will be upgrading my system in another two weeks time.... Now i have a Powersafe 400W... I cant decide what SMPS should i go for....

i cant go for antec... too costly.... nor can i go for the cheap labeled ones stating fake ratings..... so i want something in between... something like powersafe....... Please he me identify the model which would suffice my needs....

My config would be...

CPU : intel C2D 6600
asus p5ne sli
2 gb ram (upgraded to 4 gb)

8800 GTS 640 MB
soundblaster sound card
pinnacle TV Tuner
4 sata drives 200 Gb+
dvd rw ide

19 inch LCD 940BW

So what sould be the power in watts... also can some one explaing how much the voltage rating or amperes shouyld it have as i am a complete noob in this category.....:S :S :S :( :(
 
well what is ur budget for the PSU ??? if not too high u can go for the CM600 for around 3.5k ...... it should be enuff...i'm getting the same........it aint too great but it will handle ur requirements easily
 
Cooler Master eXtreme 600 is the BARE MINIMUM you should think of getting.

Retails for 4k in Mumbai.

You'll need some 30-32A on +12V and this one has 17*2=34 i.e. just enough for your requirements.
 
thats wat......i mentioned its not too great..but anything better will cost him more na.......and isnt it 3.5 from ITD ???
 
actually in Mumbai the prices of this are higher at 4k and he's from mumbai so I directly wrote 4k
 
kkk....but he can order off ITD right ??? well can u guys suggest him a better PSU in the same range, and me too ???
 
In this range this is the best PSU he can manage, regarding shipping wiith Mumbai octroi and all it'll come nearly to 4k so IMO no use on doing that; maybe someone from mumbai can shed lights on the shipping part.
 
deepak said:
actually in Mumbai the prices of this are higher at 4k and he's from mumbai so I directly wrote 4k

I've a powersafe 600w bot last yr fer 5k... Has 22x2=44W on 12v rails...

Good one... Sleeved cables n ;lots of connectors left unused...

Shud be cheaper now...
 
NMD,
Ocing or not?

Go for the Seventeam ST-500-BKP or the CM extreme power 600 which is nothing but the former retweaked to show higher peak values- 4k odd or lower now.
The former is the preffered one and do a little searching sir- lotsa 'want new rig/gpu' threads have this.

That is kinda the bare minimum imho.:ashamed:

You may try your luck with the powersafe dual rail 600 or the newer/cheapest of the lot, dual rail powersafe 500 at about 2.5k odd.:no:

deepak said:
Cooler Master eXtreme 600 is the BARE MINIMUM you should think of getting.

Retails for 4k in Mumbai.

You'll need some 30-32A on +12V and this one has 17*2=34 i.e. just enough for your requirements.
Link to the product you mentioned- where did you get those specs?:S
 
Link to the product you mentioned- where did you get those specs?

Cooler Master site didn't have the specs so I searched for a few reviews and lo and behold - the specs :D

Will link to a couple of these after sometime, gtg rite now.

BTW, can some one with more knowledge do a SMPS Buying Guide (for SMPS brands and models available in India) or something, since prices change infrequently for SMPS's this would last long too
 
deepak said:
You'll need some 30-32A on +12V and this one has 17*2=34 i.e. just enough for your requirements.

The recommended psu for a 8800gts is a 400watt supply with 26amps on 12volt lines iirc ... though getting a better one wont do any harm :P
 
^^ Yeah but he's gonna put 4 HDD's there which increase the load and may even OC the proccy which again increases the load to around 30A
 
yup thats true.......the 4 hdds......so what is the recommendation from u guys....coz i dunno about the choices of PSUs available here
 
dude get a better psu than ST 500 or CM 600....i use ST BKP 500 for my 7900gto.....and its just sufficient for the juices......

For your card and the heftier system, do consider corsair hx520 or hx620....
 
You CANT just Add up Rail ratings. You just cant.

18A on my OCZ added up (18*4 =72), would result me in having 864 Watts of power (72*12=864).

Efficiency comes into play, and not even my OCZ, not ther powersafe, not a Seventeam, can provide 18A on all 4 Rails at the same time. Max two can peak out at 18A, while 2 will be unused to lower @ 10A max.

@ gannu_rox, The Powersafe 600W would give less than 22A loaded on both rails. More like maybe 1 maxed out at 22A (which is very unlikely) and the other much lower at like 12-14A.

Alsom he doesnt need 32Amps of power. Not even when the system is fully loaded.

The CM 600W/Seventeam 500W is more than sufficient for him.
 
You CANT just Add up Rail ratings. You just cant.

Efficiency comes into play, and not even my OCZ, not ther powersafe, not a Seventeam, can provide 18A on all 4 Rails at the same time. Max two can peak out at 18A, while 2 will be unused to lower @ 10A max.

How does one calculate the total Amperage at 12V rail on a PSU then? There has to be a way no?
 
You have to bring into account the efficiency of the PSU, and other factors like Temp. which inturn affect the Efficiency, as well.

Theres only a way to estimate it, no way to get the perfect no.

My 4x12v Rails rated @ 18A each + the 3.3v Rail (36A) + the 5v rail (30A) is rated at 680W combined.

The 3.3v + 5v rails are rated 155W together.

Now, calculating the above way, ie. just adding it up, it should be 118W (3.3v) + 150W(5v) = 268W. Now why would OCZ rate it MUCH lower @ 155W?

4x18A = 864W.

864W + 268W = 1132W..

1132W + 70W (5v Backup) = 1202W

Shudnt my PSU be a OCZ ub3rXtr3m3 1200W?

Still, its rated 680W total, instead. Which is almost half the value.

Since at max. Load, thats the max. it can supply.

PSU's are rated with the Max. Output Current each rail can provide at a given time. But not when their loaded together.

ie. They can peak out at 18A, but not when others are loaded to a max. sustainable value.

If I managed to load out the PSU, all 12v Rails asking for 18A, and the 3.3v Rail asking for 36A and the 5v asking for 30A. My PSU would probably fail right there, or fluctuate so badly in voltages, that the computer would be nowhere near stable.

Hope yall understand what im yapping about. Lol.
 
Loading out the PSU is ofcourse out of the question, because at such a stage it'll fail right there and then and hence you'll never be able to actually load it.

So assuming that 155W out of the 680 go into powering the 3.3 and 5V rails at optimal load conditions (meaning say a hypothetical exact 680W is being used) then the remaining 525W go into the +12V rail right?

That should give +12V rails a total of approx 43A.

Some SMPS rate the +12V line too, IIRC the CM600 does exactly that, rating the +12V at around 400W (don't remember the exact figure).

And since CM600 is actually a 500W under max load (600 being a peak value) that seems quite possible.

And one more thing, doesn't efficiency effect how much power is actually being consumed from the wall socket.

For Eg : A 80% efficient SMPS taking 100W of power will actually use up 125W
 
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