[CentOS] Power-outage

Fri Jul 1 15:49:03 UTC 2011
m.roth at 5-cent.us <m.roth at 5-cent.us>

Blake Hudson wrote:
> From: m.roth at 5-cent.us
>> Blake Hudson wrote:
>>> From: m.roth at 5-cent.us
>>>> Nicolas Thierry-Mieg wrote:
>>>>> Colin Coles wrote:
>>>>>> On Friday 01 July 2011 12:05, Timothy Murphy wrote:
>>>>>>> Any advice or suggestions gratefully received.
>>>>>> If you are thinking of the UPS route a caveat: I have several HP
>>>>>> servers and most of them will not work on cheap UPS's as they do not
>>>>>> produce the pure sine wave modern HP machines require but rather a
>>>>>> crude stepped voltage.
>>>>> perhaps naively, I'm surprised: doesn't this mean they put crappy
>>>>> PSUs
>>>>> in those servers?
>>>>> I thought decent PSUs were expected to deal with dirty input AC?
>>>> I agree. Esp. since, other than in datacenters, *most* electric power
>>>> is
>>>> pretty crappy.
>>> I would have to disagree. They probably put high efficiency active PFC
>>> power supplies in the servers to save YOU money. You could buy a
>>> cheaper
>>> PSU that will not be as efficient and would thus cost you more in
>>> electric costs and create more heat (which would again cost you more in
>>> AC bills and reduce server density). The active PFC supplies are
>> Except that I expect datacenters to have conditioned power, and so they
>> can cheap out with the servers, with the same expectations. And I would
>> expect consumer-grade systems to not have fancy power units, but ones
>> that
>> won't die on power irregularities from the electric co's.
>> <snip>

> I think you missed the point - While manufacturer's could (and probably
> sometimes do) "cheap out with the servers" power supplies, it is not in
> your best interest (or their's).

Oh, I haven't missed the point - you missed my point, that they will cheap
out - that's in the interest of their stockholders, and their exec's stock
options. Better power supplies, though they actually cost *them* a few
dollars more, are much more expensive options.
>
> More efficient PSUs create less waste heat and draw less power which
> means higher density, more performance, etc. This is more important in
> the server space where the computers are on 24/7 and tightly packed into
> racks. More efficient PSUs cost more upfront than inefficient ones,
> which mean that Dell/HP/etc can probably make a higher profit. In the
> long term, you may be saving $50-100 per server per year on reduced
> electric and associated costs. If you're in a colo with power draw
> restrictions, you may be saving even more.

Yup. As a matter of fact, my own brand new machine here at work just
arrived an hour ago (ah, the smell of fresh plastic outgassing, factory
air from China :((( ), and when I spec'd it out, this was the option:

Precision T3500 CMT Standard PSU, C2 Motherboard [Included in Price]
Precision T3500, CMT, 85 Percent Efficient Power Supply, C2 Motherboard
[add $42.82]

You know that's maybe $5, with the quantities they're buying.

        mark