Power supply draw help
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I'm trying to calculate what my costs will be if I move my site/storage into a co-location data center. I've gotten down everything but power. I have 4 servers with 650 watt power supplies, and 4 with 450 watt power supplies. My questions start with, are they drawing 650/450 watts AC? Or is that number only relevant to the DC supply? If so, how do I go about changing that into AC wattage?
Let me know!
Thanks!
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That may be what they are capable of, but not necessarily what their average draw is.
Your best bet is to hook up something like a Kill-A-Watt and actually meter the usage during a typical load.
Someone with more EE/Power knowledge than me would probably have a more specific answer though.
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Yeah. I knew I could do that, I just don't want to buy them before I get the money for them! lol I may buy one of each just to test them. Anyways, thank you.
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You can buy an old used power meter (or even find one in a junk yard) and make yourself something alone.
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There are power supply calculators online that let you configure a system and average load, and they in turn tell you what size power supply you would need to run those components at the given load. Granted, that will only get you ballpark, but it's a start.
Many hardware review sites also test power draw on the stuff they review. See anandtech.com and silentpcreview.com for some examples.
If your servers have 650W and 450W psu, then they are almost certainly drawing something less than that. In fact, most systems will typically draw half or less of the rated max from their power supply. On the flip side, the rating is DC output, so innefficiency will dictate that the psu is drawing something more from the wall than its output.
In the end, your best bet is to meter it at the wall, as Jim said.
