<div dir="ltr"><br><br>Knute Johnson wrote:<br>> Rich Emberson wrote:<br>>> So, I recently built a new system. I figured out what<br>>> motherboard I wanted, what cpu, how much memory and<br>>> disk and then I when and used a couple of the online<br>
>> system wattage calculators and got somewhere between<br>>> 500 to 650 watts. I could not get (find) a PSU<br>>> with the right connectors for the motherboard so<br>>> I ended up getting Silverstone Zeus 750 watt supply<br>
>> (yea, overkill). I then got a UPS from a local store.<br>>> They had a sale and a higher end UPS turned out to<br>>> be cheaper than a 600 watt unit, so I got a<br>>> APC UPS BX1500LCD (865 watt) (again, overkill but nice).<br>
>> What is interesting about this UPS is that it can<br>>> show the current wattage used by your system on its<br>>> LED (along with other stuff).<br>>> Now, my strategy for constructing the new system was to pick<br>
>> a motherboard that was build for high-end power and then<br>>> pick cool components; I am a developer, not a game player<br>>> and this system will house MythTV and Asterisk someday,<br>>> well as serve as a development box.<br>
>> So, what I ended up with was:<br>>><br>>> ASUS P5Q Deluxe<br>>> Intel quad core QX9550<br>>> 95 watts max for $550<br>>> (the QX9650 is 130 watts at $1000)<br>
>> 8GB CORSAIR (DOMINATOR) TWIN2X4096-8500C5DF<br>>> Asus EN7300GT silent graphics board<br>>> idle: 8.7 Watts<br>>> max: 16.1 Watts<br>>> 2 WD VelociRaptor Model: WD3000GLFS 300<br>
>> Read/Write 6.08 Watts<br>>> Idle 4.53 Watts<br>>> Standby 0.42 Watts<br>>> Sleep 0.42 Watts<br>>> 2 WD Caviar GP Model: WD10EACS 1 TB<br>
>> Read/Write 7.50 Watts<br>>> Idle 4.0 Watts<br>>> Standby 0.97 Watts<br>>> Sleep 0.97 Watts<br>>> ASUS V60 cpu cooler (overkill)<br>>> SAMSUNG SH-S203N DVD/CD RW<br>
>> Logitech SBF-90 Black 3 Buttons 1 x Wheel<br>>> Logitech 967738-0403 Black 104 Normal Keys<br>>> SST-ST75ZF Zeus power supply (overkill)<br>>> APC UPS BX1500LCD (overkill, but very nice)<br>
>> Lian Li PC-A71 Black (overkill, but very, very nice)<br>>> BIOS 0803<br>>> Fedora 9 64<br>>><br>>> Now, with no applications running, idle, according to the UPS<br>>> the system uses 70 watts.<br>
>> The highest wattage I can get it to use running bunches of<br>>> parallel compiles is about 125 watts.<br>>><br>>> My question is: whats with the online wattage estimators?<br>>> Are they all implemented by folks selling power supplies<br>
>> who want to sell users bigger ones than are needed?<br>>><br>>> In terms of power needs, I ended up way over-specing $$ the system.<br>>> Basically, I ended up with a system that<br>>> uses as much power as a 120 watt light bulb.<br>
>><br>>> Richard<br>>><br>> <br>> Watts are simple, you just add them up. When I add up yours, I get <br>> 114.5 max load for the items you listed. I would guess then that the <br>> 125 watts you are seeing is probably pretty close. The power supply you <br>
> bought is probably bigger than you need but the UPS, if you want to run <br>> on the battery more than a couple of minutes, is probably undersized.<br><br>Turns out another part of the UPS' LED output is an estimation of how long<br>
it can support the current system at current load. For my system this time<br>varies from 60 to 70 minutues.<br><br>> <br>> If I were going to build a computer, I would probably size my power <br>> supply for twice the expected load plus a little to account for things I <br>
> don't think of. Now it is possible to put a lot of load on USB ports <br>> with external drives or other equipment so you would want to allow some <br>> more for that.<br>> <br><br>-- <br>Quis custodiet ipsos custodes<br>
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