0低功耗PC - 新的或旧的PSU

我有一台运行的服务器 24.7. 我突然想到，如果我能减少它的电力消耗，我也许可以在电费上节省一些钱. 它已经有一个低功耗的 AMD Sempron LE-1100 CPU 所以系统的功耗应该很低, 但 电源供应器 相当老旧，效率不是特别高. 这让我想到了为低功率系统设计的电源. 有很多 80+ 认证 电源供应器在那里 500+ 额定功率, 但这些真的值得为低功率系统投资吗?

My sys­tem spends most of its time idle so I decided I’d work out the power draw would be if I were to build a new sys­tem with cur­rent com­pon­ents to do it’s job..

Using the above fig­ures, I estim­ate that a new sys­tem with a sim­il­ar role and cap­ab­il­ity to what I have will con­sume just under 45watts at idle.

For a typ­ic­al low spec (450w) 电源供应器, this load is only 10%. At this low a load a typ­ic­al 电源供应器 can be quite inef­fi­cient. 该 ATX 规范要求 70% effi­ciency at 20% of rated power, but a 43W draw is below 20% rated power for all 电源供应器’s rated for 250W or above (in effect all 电源供应器的). Below is a com­par­is­on between a bare min­im­um ATX 电源供应器 和一些高效的 电源供应器的.

通用图 电源供应器 是基于最低要求，因此是最坏的情况. 即使效率很差 电源供应器 来自墙壁的交流电不会随着直流电的减少而增加. 我计算了最好的年度储蓄, 基于 10p 的 kWh 充电并假设使用率为 24.7.

结论: For a low power sys­tem it is cheap­er, and prob­ably more envir­on­ment­ally sound to keep (or re-use) an exist­ing power sup­ply than to replace it with a high power mod­el, even if the new mod­el is very efficient.

更新资料 (25-DEC-2011)

Cor­rec­ted a cal­cu­la­tion error and added the HuntKey Jump­er R90. Even a very good value, highly effi­cient 电源供应器 can­’t change the con­clu­sion much in this scen­ario — the sav­ings are just far too small to jus­ti­fy the cost (and envir­on­ment­al cost) of a new 电源供应器.  The HuntKey would take in excess of 3 years to pay for itself, and this is in an ideal scen­ario, com­pared to a a worth case scen­ario 电源供应器!  For an even lower power sys­tem (e.g. a AMD E350) the sav­ings would be lower still. Even a “per­fect” 电源供应器 would only net sav­ings of around £16 a year!