At Sun, 3 Jul 2011 00:34:18 +0100 CentOS mailing list <centos@xxxxxxxxxx> wrote: > > On Saturday 02 July 2011 21:13:59 Robert Heller wrote: > > > I'm using an UPS for my desktop system, but I don't need it for the > > > laptop. If the AC power drops, even for a moment, the laptop battery > > > will kick in and sustain the machine. I just think that the same thing > > > can be implemented for the desktop too. If I understood the OP > > > correctly... ;-) > > > > A laptop effectively contains its own UPS in the form of a power brick, > > battery and power supply on its motherboard. > > > > Yes, one *could* build a desktop or server that way, but why bother, > > since AC wall outlets are everywhere one might want to use a desktop or > > server? > > Well, one reason I can think of is that one cannot always trust the AC wall > outlet to provide uninterrupted power? By that I don't mean AC power going > down for an hour, but for a fraction of a second. > > I happen to live near an industrial zone, and every morning between 10 and 11h > someone turns on something in the nearby factory, which makes my light-bulbs > blink twice. Of course, that's enough to reboot my desktop machine no problem. > I had to buy an UPS system just because of that. Granted, an UPS turned out to > be a good investment, but still I wonder why there are no offers on the market > with a "boosted" PSU units that can sustain DC power for a couple of seconds > during the AC "blinks". They don't even need to use a battery, maybe a set of > condensers could sustain power for a short period (although I might be wrong, > never did the numbers on that). > > A friend of mine lives near the Technical Sciences university (in the middle > of the city, they don't have a campus), where they have a medium-sized wind > tunnel for the aero-engineering courses. Every time they turn the thing on, > the whole city block loses power for cca 5 seconds. Sure, it's bad AC grid > design, but bad designs are usually a fact of life. :-) > > I'm speculating here about an improved PSU device which would be more > expensive than the ordinary one, but less expensive than a typical UPS system. > Given that I believe there certainly is a market for such a PSU, I'm just > surprised nobody is selling it yet. You cannot assume that the AC wall outlet > will always provide perfect power... ;-) > > > There is (in the SciFi world) the idea that someday > > 'desktops' in the current / conventional sense may completely vanish > > from the universe, taken over progressably by laptops, tablets, smart > > phones, wearable computers (motherboard == shirt, monitor == shades, > > power supply == hat with embedded solar cells, virtual mouse/keyboard > > via motion sensors in your shirt sleves/gloves, etc.), > > I could in principle imagine all that coming in the future, but the > "monitor == shades" thing is just only Fi with no Sci in it. A human eye > cannot focus properly on any object which is closer to the eye than 10-15 cm > (depending on the eye quality), so there is absolutely no way one can use > shades or contact lenses or something similar as a monitor, regardless of > technological levels of any human or alien races (James Bond notwithstanding). > Unless of course one surgically adapts the eye lense itself, in which case the > person would not be able to see anything else... ;-) Hmmm... There were a CS prof. and some students at UMass when I was working there playing with a computer in a backpack with a 1" monitor suspended from a head mount in front of one eye. Not anything like 10-15 cm. If 10-15 cm is the minimum distance, what about telescope eyepieces, camera viewfinders (including the little video ones on camcorders), or binoculars? *I* know I can see images in the video viewfinder of my Sony Hi8 camcorder just fine, with my right up close (the old camcorder I have does NOT have a 3" swing out monitor). It is all about the optics. > > > or even > > implanted computers (eg as a thin circuit board between your skull and > > scalp, and 'wired' directly into your brain). > > I would never wire a brain to a machine. Brains make errors, are susceptible > to emotions, hormons, vanity, etc., and just introduce a large point of > failure for the otherwise-correct machines. ;-) > > > This seems to already be > > happening to some extent, in that laptops are becoming the computer of > > choise and desktops are becomming an 'old school' sort of thing. > > Yeah, the laptops are becoming cheap enough, so that once your computing needs > grow out of your current laptop, you don't even think of "upgrading" it, but > rather just buy a new model. Desktops will be in use only for custom things > (professionals who need, say, five audio cards in one machine) and small > servers. But we're getting sort-of OT here... ;-) > > Best, :-) > Marko > > > _______________________________________________ > CentOS mailing list > CentOS@xxxxxxxxxx > http://lists.centos.org/mailman/listinfo/centos > > -- Robert Heller -- 978-544-6933 / heller@xxxxxxxxxxxx Deepwoods Software -- http://www.deepsoft.com/ () ascii ribbon campaign -- against html e-mail /\ www.asciiribbon.org -- against proprietary attachments _______________________________________________ CentOS mailing list CentOS@xxxxxxxxxx http://lists.centos.org/mailman/listinfo/centos