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9 Oct 2024 16:07:56 EDT (-0400)
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From: Jim Henderson
Subject: Re: Swell.
Date: 10 Nov 2009 10:13:31
Message: <4af9831b$1@news.povray.org>
On Tue, 10 Nov 2009 07:38:30 +0000, Orchid XP v8 wrote:

> Wanna take a guess what the customary place to install programs is?
> Yeah, it's C:\Program Files.

Then there's also the button that lets you choose a different location to 
install to - part of pretty much every modern installation program on 
Windows.

Jim


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From: Jim Henderson
Subject: Re: Swell.
Date: 10 Nov 2009 10:16:57
Message: <4af983e9$1@news.povray.org>
On Tue, 10 Nov 2009 10:21:30 +0000, Invisible wrote:

>>> ...yeah, shopping online tends to be cheaper. Quality is another
>>> matter, of course.
>> 
>> Buy from reputable dealers, and quality isn't an issue.
> 
> I don't mean to imply that quality is *necessarily* an issue, just that
> it *can* be more of an issue. As you say, it depends who you buy from.

Exactly.  I started using newegg because system builders I know who build 
for small businesses used them.  I rarely go to a place I've never heard 
of and bought something.  Oddly, the svideo cable I mentioned before I 
did go to a relatively unknown company - but I didn't drop more than 
about 10 bucks on the cable, either, and when I do something like this, I 
usually start with something cheap.  I did this with a place that sold 
through Amazon - bought a $3 iPod battery replacement kit - that worked, 
so ordered a laptop battery from them for my stepson's laptop.  Both have 
worked well. :-)

> I often buy from Maplin because 1) I don't have to wait for it to be
> delivered, 2) their staff actually have a frickin clue, and 3) they
> don't argue about returns.

Sometimes expediency is worth the extra cost - as is the ability to get 
something replaced without a hassle.

Jim


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From: scott
Subject: Re: Swell.
Date: 10 Nov 2009 10:18:51
Message: <4af9845b$1@news.povray.org>
> In theory, until the disks are spinning at full speed, you don't get that 
> "cushion of air" for the heads to "fly" on, which should result in wear. 
> Of course, no doubt manufacturers know all about this and have come up 
> with ways to at least reduce the problem...

There's probably just a reserved portion of the platter that is used for 
spin-up/down operations.  The only tricky bit is to get the head over to 
that portion when the power is suddenly cut.


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From: Invisible
Subject: Re: Swell.
Date: 10 Nov 2009 10:25:20
Message: <4af985e0$1@news.povray.org>
>> Tape operates at much lower speeds. And since the only people who use
>> tape are people who want seriously reliable backup storage, it tends to
>> be very well engineered. (And stupidly expensive...)
> 
> Never used DAT drives for backup, have you? ;-)

No, only for the last 6 years.

> Horrible quality of storage media, and terrible shelf life IME.

Really?


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From: Invisible
Subject: Re: Swell.
Date: 10 Nov 2009 10:27:59
Message: <4af9867f$1@news.povray.org>
>> I often buy from Maplin because 1) I don't have to wait for it to be
>> delivered, 2) their staff actually have a frickin clue, and 3) they
>> don't argue about returns.
> 
> Sometimes expediency is worth the extra cost - as is the ability to get 
> something replaced without a hassle.

Maplin are pretty much the best electronics shop around.

I mean, apart from being the *only* place in all of Christendom which 
can sell you (say) a 50kohm resistor, their staff have a clue about what 
they're supposed to be selling, and if you take something back they will 
exchange it or give you your money back (provided it isn't obviously 
busted).

Their website utterly sucks, by the way...


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From: Invisible
Subject: Re: Swell.
Date: 10 Nov 2009 10:32:46
Message: <4af9879e@news.povray.org>
>> In theory, until the disks are spinning at full speed, you don't get 
>> that "cushion of air" for the heads to "fly" on, which should result 
>> in wear. Of course, no doubt manufacturers know all about this and 
>> have come up with ways to at least reduce the problem...
> 
> There's probably just a reserved portion of the platter that is used for 
> spin-up/down operations.

I'm 98% certain this is the case. However, that still means that this 
part of the disk wears down, and also that the heads themselves wear down.

> The only tricky bit is to get the head over to that portion when the
> power is suddenly cut.

This is probably fairly trivial. In the old days you used to have to run 
the "park" command. But today... well, have you ever noticed that 
"click" noise when you unplug the power? I imagine that's the magnet in 
the voice coils parking the heads. ;-)

In fact, I've disassembled a HD and observed that the arm strongly 
resists any attempt to remove it from the home position. It keeps 
wanting to click back into place, with the heads on the outer edge of 
the platters.


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From: Invisible
Subject: Re: Swell.
Date: 10 Nov 2009 10:33:52
Message: <4af987e0$1@news.povray.org>
>> Wanna take a guess what the customary place to install programs is?
>> Yeah, it's C:\Program Files.
> 
> Then there's also the button that lets you choose a different location to 
> install to - part of pretty much every modern installation program on 
> Windows.

There is *usually* such a button, yes. Not always though.

And it's not unheard-of for a program to malfunction if you change this 
setting during installation. (You'd think if they offered you the 
option, they'd implement it so it works. But not always...)


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From: Aydan
Subject: Re: Swell.
Date: 10 Nov 2009 10:35:01
Message: <web.4af98757a6cd6561ccf29180@news.povray.org>
"scott" <sco### [at] scottcom> wrote:
> > In theory, until the disks are spinning at full speed, you don't get that
> > "cushion of air" for the heads to "fly" on, which should result in wear.
> > Of course, no doubt manufacturers know all about this and have come up
> > with ways to at least reduce the problem...
>
> There's probably just a reserved portion of the platter that is used for
> spin-up/down operations.  The only tricky bit is to get the head over to
> that portion when the power is suddenly cut.

I think they don't park the heads on the platter any more, they're moved out of
the platter radius before spindown.
Moving the head out of the way in case of power failure is not so problematic
I'd think. The positioning coils of the heads are constantly under current and
cutting this current will create a force. You "just" have to make it so that a
power failure exerts a force in the head mechanism that whips the head into
park. ;o)


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From: Aydan
Subject: Re: Swell.
Date: 10 Nov 2009 10:35:01
Message: <web.4af98774a6cd6561ccf29180@news.povray.org>
Jim Henderson <nos### [at] nospamcom> wrote:
> On Mon, 09 Nov 2009 16:53:14 +0100, clipka wrote:
> > I wouldn't be too much surprised if HDD manufacturers would know ways
> > how to optimize drives for one usage pattern or the other, so that maybe
> > indeed powering up and down might kill a server HDD quickly, while 24x7
> > usage might shorten the life of an office computer / consumer HDD.
>
> That seems to be reaching to me.
>
> Jim

Not that reaching. WD sells HDs which are specifically for 24/7 usage.
I think the difference is the lifetime of the bearings which is dependent not so
much on actual age but on revolutions and temperature.


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From: Invisible
Subject: Re: Swell.
Date: 10 Nov 2009 10:35:27
Message: <4af9883f$1@news.povray.org>
Stefan Viljoen wrote:

> This is what always bursts my bubble about space travel - whenever I hear of
> the incredible distances involved. 

The distances are *astronomical*!

Literally. As in, that's where the term comes from. ;-)

> it is still 4 YEARS in space to the nearest start.

I'm glad it's not just me who constantly mis-spells "star". :-D

> To even get to more "close" stuff, 6 YEARS, 10
> YEARS - or -thousands- of years (at LIGHTSPEED!) to another galaxy.

Indeed. Without warp drive and the ability to vastly exceed the speed of 
light, it will just take such an absurdly long time to go anywhere that 
it doesn't bare thinking about. Think about it: how long ago did we land 
on the moon? And how long after that did we land on Mars? Oh, wait...

In fact, half the stars in the night sky probably DON'T EVEN EXIST ANY 
MORE. It's just that it's taken that long for the light to reach us.

> Of course, time dilation at high relativistic velocities might mean you can,
> from your relative viewpoint, complete the journey within a human lifespan
> of 70, or 80 years, depending on just how close you can get to the
> magical "c". Nothing would be left back home though, since thousands of
> years might have passed there...
> 
> It just somehow... sad.

Yeah.


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