The 1KW PSU has come :D

[TeePee]

Watts, probably. My system 'needs' 450W, but runs rock steady on the 300W generic PSU that came with my case 5 years ago.

I guess some people just buy into the hype.

[PMM]

1st Most manufactures are mis-leading with there PSU ratings

A 450watt PSU maybe rated at 450watts at 25deg however most supplies run
warm so that figure degrades.

Good example is the Qtec 550watt which in real terms works out at about 315watts
on the top end before the voltages dive.

2nd The wattage specified is the combined output of all voltage rails +3.3 +12 +5 -12
your computer is not going to use them rails equally

So unless you know how you equipment uses its power and which rails it stresses
it can be very easy to exceed the limits of one of those rails esp. as not all PSU's
are equal in there abilities.

So there are situations where a PSU will need to be rated higher than the requirements of the PC to make sure a percific voltage rail meets the needs of the drain on it.

Its fact there there are manuafactures that are good with there ratings and there are
PSU's out there that may exceed there spec and then there are others that fail big time.

I've seen computers keel over while not using the rating of there PSU purely because
one of the rails have made there limit while the others have been fine.

It's also not good to run PSUs near there limit the stresses can cause more rapid degradation of its internals over time.

So not so much hype, but maybe luck for some in that they have a balanced system or that they have a PSU that working better than its rating suggests.... or they could be on the edge of a critical system failure without knowing it.

[iranu]

What are "A"? It obviously cant be amps...so what it is?

http://en.wikipedia.org/wiki/Ampere

I can't beleive you would need 30A on the 12v rail to run a single x1900xt(x).

PMM's point is very valid. My brother just lost his socket a mobo, geforce 4 and 2 hd's to a generic 300w 5 year old psu dying. When I picked up the psu a small capacitor fell out of it!! His system was not drawing anymore than 172W and did not require any more than a 250w psu. It ran perfectly until the day he switched it on and the psu died.

More expensive (read higher quality) psu's tend to have higher quality components that are able to take the strains of startup and heat much better than cheaper models. The lesson is don't skimp on the cost of a psu. Buy a high quality lower watt model rather than a 550w Q-tec!

[PMM]

I take what they say as being a recommendation, facturing in typical systems
requirements.

The Cards themselves will not require that, but the system in the whole might do.

Going purely by the quote above.. a card is using around 100watts based on them
saying 2 cards requires 8 amps more than using a single on the 12v rail not factoring
any supplyed by the motherboard on any 3.3v or 5v rail.

That's when there stressed 100%

so in an example of
X2 4800 = 110watts (Loaded)
2 * ATi = 200 watts+ (Loaded)

Not factoring in anything else that's 310+ watts

You than have to factor in other requirements of the motherboard / ram /
harddrives / Fans / other plug in cards.

[PMM]

With a price tag of ~500 bucks it'll cost something like 450 quid over here, that's insane for a PSU.

£350 + vat (Available in the UK)

[TeePee]

Still some believers?
The only website I really trust to give real world information on this wrote this.

...sites like ours will harp on at you time and time again that it's not the output power rating of the PSU you should be caring about....

[Twigman]

http://en.wikipedia.org/wiki/Ampere

I can't beleive you would need 30A on the 12v rail to run a single x1900xt(x).

Considering all the sockets in every standard domestic house i have ever been in have 13Amp fuses on, I dont think its amps...hence my doubtfulness in my first post.

[5lab]

Considering all the sockets in every standard domestic house i have ever been in have 13Amp fuses on, I dont think its amps...hence my doubtfulness in my first post.

thats 13amps at 230volts.. for sake of argument lets say thats 240volts - 13 amps there is the equivilant of 260 amps at 12 volts (if my gcse physics serves me correctly - please say if i'm wrong..)

[PMM]

Considering all the sockets in every standard domestic house i have ever been in have 13Amp fuses on, I dont think its amps...hence my doubtfulness in my first post.

That's Amps at the voltage its supplying

You have to separate input power from output power

A PSU for example say consuming 600 Watts @ 240v would only require 2.5Amps
if it was fully supplying to its maximum.

However on the outputs your 240Volts is reduced down to your 12v / 5v & 3.3v etc
and the current increases (-Minus overheads) (Assuming all that power was available
at 12v) you would get something like 48amps @ 12v

However that's would never be the case based on the fact part of the load is made up
of the drain for the 5v & 3.3v lines.

/hope that makes some form of sense.

If not hope this does http://computer.howstuffworks.com/power-supply.htm

[8bit]

My rig (see specs) needs 360w according to the outervision calc running at 100% CPU and GFX. It's a gaming rig so it mostly is running at 100%. That's specifying my raptor as a 10krpm SCSI drive since there's no option for 10krpm SATA so I suspect it would be a bit less than that TBH.

I've never believed the hype about needing hundreds of watts for a regular gaming PC. My Dell at work has a P4 @ 2GHz, 3 sticks of RAM, 2 hard disks, a Quadro FX graphics card and about 4 USB powered devices on a 225w PSU... and that's a P4!

[TheAnimus]

also remeber its ment to be 220V RMS (root mean square) so its actually over 300 peek. But AC voltage is a fun thing to calculate.

Most components suck power on the 12v rail. Myself i recomend getting a good quailty higher rated PSU, as the PSU should be able to run cooler, if its only running at 50% max output.

A good example is my desktop, dual neccona xeons 3.0ghz. Instantly 200w there. according to the datasheets. Add in 5 15k rpm hdds and we instantly in dual PSU teritory just to keep the load down. Thing is, i dislike the idea of so much heat been disapated in a small ATX Spec PSU. No PSU is 100% efficent, even under its most perfect load condition, and whilst these PSU's are "switch mode" (their characteristics change depending on load) theres still a fair bit of heat thats going to be disapated on a 1kw PSU.

[Twigman]

Oh ok...i read it as:

"you need 450W with 30A [input] for a single card while you need a minimum of 550W PSU providing 38A for two cards"

which i guess is wrong now.
Furry muff.

[chilled]

Power calculators

http://www.jscustompcs.com/power_supply/

http://extreme.outervision.com/index.jsp (more upto date)

According to outervision I will need 460w (assuming 80% psu utilisation) for the following

opteron 146 @ 3ghz hopefully (so used FX57 value)
2x 7800gtx (if I choose to buy another)
2 sticks ram
1 dvd rom
1dvd/cd rw
1 floppy
2x sata hd
1x ide hd
3x 120mm led fans

I bought a 480w tagan 18 months ago for my current system knowing that power consumption will go up. I think that a high quality psu with some headroom is one of the best investments you can make.

I certainly would not want to run anything more than 80% of the psu wattage or 80% ampage on the 12v rail as manufacturers often quote their psu's peak power output which is unsustainable. Those that say you can get away with a 300w psu are not correct if running a modern a64 gaming rig!

Incidentally the inquirer is quoting a site who have tested ati's x1900xt(x) cards

"you need 450W with 30A for a single card while you need a minimum of 550W PSU providing 38A for two cards"

http://www.theinquirer.net/?article=28611

Not sure that I believe that cos that's huge Amps! As for 1k it's a bit like having 1k horsepower in a car - never gonna use it but you'll win in the bragging wars.

NV said something similar for the 6800U. The Inq also exaggerates at the best of times. Having said that, there's a difference between quality PSUs and high amp rated junk.