Web site for calculating PSU needs

PSUs: The source of DC power for all components in the PC & often a big noise source.

Moderators: NeilBlanchard, Ralf Hutter, sthayashi, Lawrence Lee, Devonavar

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Wedge
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Web site for calculating PSU needs

Post by Wedge » Sat Mar 26, 2005 8:27 am


MikeC
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Post by MikeC » Sat Mar 26, 2005 9:30 am

That's a reasonably good calculator -- if you take the max number it spits out as the rating of the PSU you need. With the hottest AMD/Intel CPU & vidcard + 2 of the hottest & most power everything else, it adds up to ~400W. That's the max you'd get if every component in the system could be made to draw max power simultaneously -- which is just about impossible to do. But given the need for some headroom, using this calculator's number as the PSU rating guide is probably good.

|Romeo|
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Post by |Romeo| » Sat Mar 26, 2005 10:46 am

I'd love to know where their USB device power consumption is coming from; +5V, 500mA* equals a power draw of 5W...

*Yes, I know that laptops often allow more than 500mA for CD drives, but they're the exception and I believe that they all negotiate that, rather than the laptop just supplying it.

StarfishChris
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Post by StarfishChris » Sat Mar 26, 2005 11:09 am

Good to see an updated power calculator. Maybe you should link to it in a sticky?

Some USB ADSL modems (the ones BT provide definitely) were said to need about 700mA, and wouldn't work with some USB interfaces for that reason. However I would estimate that only about 1-2 devices you have will actually be powered by USB. (Webcam, HIDs, audio devices are the only other things I can think of right now.)

For the most part this is just a minor point, though :)

Qwertyiopisme
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Post by Qwertyiopisme » Sat Mar 26, 2005 11:22 am

Um, either my DNS doest have that site or it is dead.. Could someone post the IP of that site so I can test? (Gothenburg (Sweden), Bredbandsbolaget)

Devonavar
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Post by Devonavar » Sat Mar 26, 2005 11:26 am

IP: 207.44.178.47

nici
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Post by nici » Sat Mar 26, 2005 2:59 pm

I cant get to the site, it says that the connection timed out.. I tried it earlier too when someone posted it at a different site. Same problem with IE and Firefox.

CX23882-19
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Post by CX23882-19 » Sat Mar 26, 2005 3:14 pm

Doesn't work for me either (Vispa ADSL)

wooglin
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Post by wooglin » Sat Mar 26, 2005 4:07 pm


m0002a
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Post by m0002a » Sat Mar 26, 2005 5:03 pm

Just for grins, I ran my PIII 866 Gateway machine through the calculations:

Intel 815 Motherboard
P-III 866 (includes HSF with 80 mm Panaflo with Fanmate)
32 MB AGP video (GeForce2 GTS)
Three sticks PC133 RAM (512 MB)
Two IBM Disk Drives (30 GB and 60 GB)
Plextor 12X CD/RW
Pioneer 4X DVD ROM
PCI card - 3COM Ethernet
PCI card - USB ports (4)
PCI Sound Blaster Live
USB Keyboard
USB Cable Modem
USB connection to APC UPS
80 mm rear case fan (Thermaltake)

Total recommended watts = 250

I bought this machine in June 2000, and it is still going strong with the original 200 watt power supply (SFX form factor). I replaced the internal 92 mm PSU fan about 1 year ago with a Panaflo Medium runing about 7 volts on a Fanmate.

acaurora
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Post by acaurora » Sat Mar 26, 2005 6:15 pm

Hmmm... interesting. Says with my setup, 351W!!!! That 6800U uses the same amount of power as my 3200 Athlon XP Barton . . . *jaw drop*.

........ DANG.

Okatha
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Post by Okatha » Sat Mar 26, 2005 9:49 pm

Mine is supposedly at 343 Watts. No wonder it's pretty warm, heh.

One thing I'm a little confused on is does it count the HSF for the video card in their power calculations, or do you need to add an extra system fan? Theoretically it's only a couple watts either way, just something that snagged my brain when I was looking at it.

Either way, cool find. Thanks.

rpsgc
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Post by rpsgc » Sun Mar 27, 2005 2:01 am

Isn't working for me.

Qwertyiopisme
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Post by Qwertyiopisme » Sun Mar 27, 2005 2:19 am

Hmmm, my DNS isn't not making it work, neither the IP nor the url works... Strange...

charger2000
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Post by charger2000 » Sun Mar 27, 2005 2:58 am

sorry, but there's something REALLY wrong in those numbers, eg:

AMD Athlon 64 , 89 Watts
Intel Pentium IV 520, 78 Watts
Intel Pentium IV 530-560, 90 Watts

:shock:

from Anandtech:

config:
AMD Athlon 64 Configuration

Socket-939 Athlon 64 CPUs
2 x 512MB OCZ PC3200 EL Dual Channel DIMMs 2-2-2-10
NVIDIA nForce4 Reference Motherboard
ATI Radeon X800 XT PCI Express

Intel Pentium 4 Configuration

LGA-775 Intel Pentium 4 and Extreme Edition CPUs
2 x 512MB Crucial DDR-II 533 Dual Channel DIMMs 3-3-3-12
Intel 925XE Motherboard
ATI Radeon X800 XT PCI Express

Image
Image

StarfishChris
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Post by StarfishChris » Sun Mar 27, 2005 5:53 am

They've used the guideline figures, Intel give 'typical' (hah) and AMD the maximum - neither are accurate (~20W above for Intel, below for AMD).

Ralf Hutter
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Post by Ralf Hutter » Sun Mar 27, 2005 7:02 am

That's certainly the most rational PSU "calculator" that I've ever played with. It actually spits out some fairly accurate numbers.

*bookmarked*

Ackelind
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Post by Ackelind » Sun Mar 27, 2005 8:20 am

The site doesn't work for me either.. must be because I'm in sweden or something.

|Romeo|
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Post by |Romeo| » Sun Mar 27, 2005 8:47 am

Well I certainly don't think it's bad; the double error only apears to happen for USB; the rest of the numbers seem to be about right. It's just a shame that more companies don't make the information about their products easily available <cough>graphics card, sound card, RAID card, chipset... </choke on too much coughing>

Mats
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Post by Mats » Sun Mar 27, 2005 9:07 am

StarfishChris wrote:They've used the guideline figures, Intel give 'typical' (hah) and AMD the maximum - neither are accurate (~20W above for Intel, below for AMD).
The same for mobiles? Of course not 20 W+ on a Pentium M but maybe 15 - 25 %?

davidstone28
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Post by davidstone28 » Sun Mar 27, 2005 11:03 am


Ackelind
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Post by Ackelind » Sun Mar 27, 2005 12:16 pm

Nice, too bad it was so outdated, seems to have been written even before pci-e was introduced.

CX23882-19
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Post by CX23882-19 » Tue Mar 29, 2005 9:45 am

I checked the 1st site from work and it loaded fine and gave a power consumption of 330W for my system. I know that PSU's fan controllers are dependent on temperature rather than the actual load (although temperature is dependent on load), but SPCR give Watts vs dB ratings, so am I unlikely to get any PSU running at under 30dB (stock) with my system?

Even with adequate airflow my Nexus NX-4090 is still loud for me compared to the rest of the system.

tay
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Post by tay » Tue Mar 29, 2005 12:24 pm

davidstone28 wrote:http://takaman.jp/D/?english

load per rail
The hd numbers seem a bit high, but overall numbers came out pretty close to the first calculator. About 260 watt for both for my system which is higher than I would've thought but I dont burn cd/defrag hdd/play quake at the same time.

Interesting just how little is coming from the 3.3v rail and the mediocre requirements of the 5v rail.

Tephras
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Post by Tephras » Tue Mar 29, 2005 4:18 pm

CX23882-19 wrote:I checked the 1st site from work and it loaded fine and gave a power consumption of 330W for my system. I know that PSU's fan controllers are dependent on temperature rather than the actual load (although temperature is dependent on load), but SPCR give Watts vs dB ratings, so am I unlikely to get any PSU running at under 30dB (stock) with my system?

Even with adequate airflow my Nexus NX-4090 is still loud for me compared to the rest of the system.
You have to remember that the figures provided by the power calculator(s) are calculated with the assumption that every component in the computer is running at full load at the same time, a situation that most likely won't happen. Under normal operation your system will not reach those 330W, so finding a PSU with a noise level below 30dBA during normal system load won't be a problem.

|Romeo|
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Post by |Romeo| » Wed Mar 30, 2005 8:25 am

tay wrote: The hd numbers seem a bit high
The nice thing about HDs is that the information on power consumption is fairly easy to get.

Slaugh
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Post by Slaugh » Wed Apr 20, 2005 12:26 am

I just found another site for PSU wattage calculation, the eXtreme PSU Calculator v1.1:

http://www.extreme.outervision.com/index.jsp

There are more options than the "Journey Systems Power Supply Calculator" and extra calculations for watercooling and overclocking (it doesn't work for underclocking though). According to them, my system draws 296W (maximum peak)... The "Journey Systems Power Supply Calculator" gives a lower number, with 265W (maximum peak) for the same system.

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