power supply calculator calculations

John Doe · Dec 1, 2008

Power supply calculators mostly from well-known names/brands.

Calling my mainboard/motherboard "regular desktop".
two core CPU
NVIDIA 7950GT (no 512MB option)
two PCI cards (sound and NIC)
combo CD drive
one SATA hard drive
three USB devices
three fans

http://extreme.outervision.com/PSUEngine
231 Watts

Included quad core Intel Q9550 CPU.

http://support.asus.com/PowerSupplyCalculator/PSCalculator.aspx?
SLanguage=en-us
350 Watts

http://global.msi.com.tw/index.php?func=power
This one asks for the CPU Code, but makes no difference.
357 Watts

http://www.thermaltake.outervision.com/
269 Watts

Dave · Dec 2, 2008

John Doe said:
Power supply calculators mostly from well-known names/brands.

Calling my mainboard/motherboard "regular desktop".
two core CPU
NVIDIA 7950GT (no 512MB option)
two PCI cards (sound and NIC)
combo CD drive
one SATA hard drive
three USB devices
three fans

http://extreme.outervision.com/PSUEngine
231 Watts

Included quad core Intel Q9550 CPU.

http://support.asus.com/PowerSupplyCalculator/PSCalculator.aspx?
SLanguage=en-us
350 Watts

http://global.msi.com.tw/index.php?func=power
This one asks for the CPU Code, but makes no difference.
357 Watts

http://www.thermaltake.outervision.com/
269 Watts

Well all of those are estimates obviously, and the average is about 275W.
So your power supply should be a good name-brand of about 650W. You don't
want to run your power supply at maximum capacity constantly, you want to
keep it around the ~40% range. -Dave

John Doe · Dec 2, 2008

Well all of those are estimates obviously,

Estimates of the required power supply wattage, Dave.

and the average is about 275W. So your power supply should be a
good name-brand of about 650W.

Only if you sell power supplies, Dave.

If you have some other respected names that provide power supply
calculators, provide the links and I'll post more results.

Dave · Dec 2, 2008

John Doe said:
Estimates of the required power supply wattage, Dave.

Then they are all broken. Who are you going to believe...some random web
site calculators or the makers of the hardware? Minimum for any current
build is 450W power supply (not according to ME, BTW). If the calculators
you quote are all BELOW that, then they are all broken. AVERAGE power usage
for a mid-range system today (not power supply size!) is 275W continuous.
Are you going to run that off of a 231, 350, 357 or 269W power supply? OK,
the 350 or 357 might handle it, assuming the right load balance on the
various rails (highly unlikely) and assuming you think it's OK to run a
power supply at 80% of it's maximum rating, continuously.

Only if you sell power supplies, Dave.

I don't sell power supplies. If you want to buy a power supply that is four
sizes too small, feel free. Just be sure to keep a spare on hand, as you
are going to need it within a few months...
Oh, and after you find out the hard way that your original was way too
under-powered, think about maybe choosing the right one next time around.
Or not. I mean, if you want to buy three or four power supplies for one
system, who am I to stop you?

If you have some other respected names that provide power supply
calculators, provide the links and I'll post more results.

I don't put much faith in the power supply calculators as my current build
ranges from 340W to 819W. I chose an 800W power supply which is definite
overkill, but I got such a good deal on it that even a good quality 650W
(more appropriate) would have been more expensive.

Look, I'm not going to hold a gun to your head to force you to do the right
thing. But before you buy your power supply, keep in mind that good quality
name-brand 550W power supplies start below $50...so there's really no good
reason to buy one smaller. -Dave

John Doe · Dec 2, 2008

Dave said:
Then they are all broken.

Says who, Dave?

Who are you going to believe...some random web site calculators or
the makers of the hardware?

Try reading the post you reply to, Dave.

Minimum for any current build is 450W power supply (not according
to ME, BTW).

According to whom, Dave?

and assuming you think it's OK to run a power supply at 80% of
it's maximum rating, continuously.

Again... the calculated wattage is not for typical usage, Dave, it
is for recommended power supply wattage.

I don't sell power supplies.

Sounds like you sell something, Dave.

If you want to buy a power supply that is four sizes too small,
feel free.
BZZZZT!!!
Wrong.

Just be sure to keep a spare on hand, as you are going to need it
within a few months...

BZZZZT!!!
Wrong again.

Oh, and after you find out the hard way that your original was way
too under-powered,

BZZZZT!!!
Wrong again.

Or not. I mean, if you want to buy three or four power supplies
for one system,

BZZZZT!!!
Wrong again.

I've been using the same Antec True Power II 380 W for years.

By the way, Dave, are you the one that said I must buy a new power
supply when upgrading to an Intel E6850 system?

I didn't mention it before... but BZZZZT!!! Wrong again.

There seems to be a pattern here, Dave.

I don't put much faith in the power supply calculators

Besides your own opinion, Dave, what do you put your faith in?

Look, I'm not going to hold a gun to your head to force you to do
the right thing.

Not unless you're in a movie.

Your opinion is obvious, Dave, try providing some citations.

But before you buy your power supply, keep in mind that good
quality name-brand 550W power supplies start below $50...so
there's really no good reason to buy one smaller.

You get what you pay for, Dave.

Dave · Dec 3, 2008

John Doe said:
Says who, Dave?

Try reading the post you reply to, Dave.

According to whom, Dave?

Again... the calculated wattage is not for typical usage, Dave, it
is for recommended power supply wattage.

Sounds like you sell something, Dave.

BZZZZT!!!
Wrong.

Why do I get the feeling that if I told you to change the oil in your car
every 3000 miles, you'd argue the point?
Dude, I am extremely knowledgable about computer hardware. I don't care
whether you believe that or not. But my point is, I am honestly trying to
help you by giving you GOOD advice about a possible future hardware
purchase. Ignore me at your own peril. Ok, I'm done with you. -Dave

John Doe · Dec 3, 2008

....

I am honestly trying to help you by giving you GOOD advice about a
possible future hardware purchase. Ignore me at your own peril.
Ok, I'm done with you.

Why? I've seen much longer (entirely unsubstantiated) arguments.