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Invisible <voi### [at] dev null> wrote:
> I don't know, man. SSD is still too expensive for anyone except
> performance freaks. More bafflingly, even though the performance of SSD
> should be orders of magnitude superior to HD, apparently some of the
> best HDs can actually surpass SSD. That shouldn't be possible, but
> somehow it is. I find that utterly bizarre, but those are apparently the
> numbers.
Well I have two SSDs and I'm not a performace freak.
> More bafflingly, even though the performance of SSD
> should be orders of magnitude superior to HD, apparently some of the
> best HDs can actually surpass SSD. That shouldn't be possible, but
> somehow it is. I find that utterly bizarre, but those are apparently the
> numbers.
Depends on what key parameters youre looking at. In sheer bulk transfer rate and
especially write speed, it's possible for a mechanical drive to outperform an
SSD.
But for random access you'll be hard pressed to find a mechanical drive
outperforming an SSD.
And that's the main reason I have my SSDs. For the random access speed.
My SSDs have a random access speed in the low megabyte range, but thats still 10
times faster than my mechanical ones (late model 1 & 2 TB Western Digital SATA2
drives).
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On 08/03/2012 12:42 PM, Invisible wrote:
>>>> You could just as well ask why don't they make 64TB drives right now.
>>
>>> Yep, I'd be interested to hear the answer to that one too.
>>
>> Did you know that technology has to first be developed before it can
>> be used?
>
> OK. So why spend time and money developing a 32TB drive when you could
> just go develop a 64TB drive instead?
Several years ago I used to work for Motorola in one of their
semiconductor factories. I seem to remember that there was covered
switch that when thrown would change the factory output from DIL CMOS
chips to microprocessors without having to go through the process of
designing the new chips or retooling the factory. It also connected the
new suppliers. </leg_pull>
--
Regards
Stephen
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Am 08.03.2012 12:44, schrieb Invisible:
> I can understand how something /complicated/ - like, say, a processor -
> would take time. Inventing a new feature takes a lot of R&D. But just
> making the transistors smaller? I don't really see why they have to
> shrink in tiny little baby steps. Why not just go the whole hog straight
> away?
Because maybe - just maybe - they have to /find out/ how to make that
next "tiny little baby step"? After all, they're creating structure
sizes nowadays where naive classic photolitpgraphy with ~400 nm UV light
would fail utterly. Remember that old rule that you can't etch
structures smaller than the wavelength of the light you're using?
Some of the "baby steps" involved:
- Replacing the ~400 nm Hg vapor lamps with ~250 nm KrF excimer lasers.
Obviously you need to figure out how to build an excimer laser for this
feat. You may also need to develop new optical materials (in case the
old ones absorb the new wavelength) and/or new photoresists (in case the
old ones are insensitive to the new wavelength).
- Replacing the ~250 nm KrF excimer lasers with ~200 nm ArF excimer
lasers. Obviously you need to extrapolate your excimer laser design to
use ArF, and again you may need new optical materials and/or photoresists.
- Replacing the liquid etching agent with plasma, to reduce undercutting
of the photoresist. Obviously you need to figure out that plasma etching
will have these benefits in the first place, and then find ways to
handle the plasma in the fab.
- Exposing the photoresist in liquid rather than in air or vacuum, to
reduce wavelength accordingly. Obviously you need to find a suitable
liquid with high purity, and figure out how to handle it in the fab.
- Designing masks in such a way that they no longer directly correspond
to the desired structures, but rather cause interference patterns of the
desired shape. Obviously you need to develop suitable algorithms to
generate the masks from the desired structures, and you probably need
quite some computing power to pull this off.
Other steps may involve improvements of photoresists and application
techniques (you want a thin yet uniform coating, which adheres well to
the wafer) plus suitable developer, etching and resist stripping agents;
improvements in wafer cleaning processes; reduction of mechanical
tolerances; and other some such. Much of this goes into overcoming
problems that hadn't been anticipated before.
Last not least, there's also the question of cost: Using cutting-edge
technology for memory ICs would result in prohibitively high per-bit
costs; such production lines are therefore almost exclusively used for
high-margin products such as high-performance CPUs or GPUs, until the
next generation of cutting-edge fab technology becomes available. The
older production lines might then be used for another generation to
manufacture low-cost CPUs and GPUs, and finally for stuff where
per-transistor costs are more important than die size, such as memory ICs.
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On 08/03/2012 02:50 PM, Aydan wrote:
> Invisible<voi### [at] devnull> wrote:
>> I don't know, man. SSD is still too expensive for anyone except
>> performance freaks. More bafflingly, even though the performance of SSD
>> should be orders of magnitude superior to HD, apparently some of the
>> best HDs can actually surpass SSD. That shouldn't be possible, but
>> somehow it is. I find that utterly bizarre, but those are apparently the
>> numbers.
>
> Well I have two SSDs and I'm not a performace freak.
You clearly have a hell of a lot more money than I'll ever have.
Or rather, you /had/ a lot of money... ;-)
>> More bafflingly, even though the performance of SSD
>> should be orders of magnitude superior to HD, apparently some of the
>> best HDs can actually surpass SSD. That shouldn't be possible, but
>> somehow it is. I find that utterly bizarre, but those are apparently the
>> numbers.
>
> Depends on what key parameters youre looking at. In sheer bulk transfer rate and
> especially write speed, it's possible for a mechanical drive to outperform an
> SSD.
> But for random access you'll be hard pressed to find a mechanical drive
> outperforming an SSD.
> And that's the main reason I have my SSDs. For the random access speed.
You would expect an SSD to blitz a HD for random access. But even just
for read access, you would have expected a purely electronic device to
be many billion times faster than a mechanical HD. And they aren't, for
some reason...
Write performance is another matter. Apparently you have to bulk-erase
cells before you can write them again. So I can understand that being
slower. Even so, you'd think some kind of parallel processing
arrangement could hide some of that...
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On 08/03/2012 03:23 PM, clipka wrote:
> Last not least, there's also the question of cost: Using cutting-edge
> technology for memory ICs would result in prohibitively high per-bit
> costs; such production lines are therefore almost exclusively used for
> high-margin products such as high-performance CPUs or GPUs, until the
> next generation of cutting-edge fab technology becomes available. The
> older production lines might then be used for another generation to
> manufacture low-cost CPUs and GPUs, and finally for stuff where
> per-transistor costs are more important than die size, such as memory ICs.
Right. So that's why, even though 40nm technology already exists, they
don't use it just to build (say) USB flash drives. (?)
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On 08/03/2012 3:53 PM, Invisible wrote:
> to be many billion times faster
Do you really mean "billion"? :-P
--
Regards
Stephen
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Invisible <voi### [at] devnull> wrote:
> On 08/03/2012 02:50 PM, Aydan wrote:
> > Well I have two SSDs and I'm not a performace freak.
>
> You clearly have a hell of a lot more money than I'll ever have.
>
> Or rather, you /had/ a lot of money... ;-)
>
> You would expect an SSD to blitz a HD for random access. But even just
> for read access, you would have expected a purely electronic device to
> be many billion times faster than a mechanical HD. And they aren't, for
> some reason...
>
> Write performance is another matter. Apparently you have to bulk-erase
> cells before you can write them again. So I can understand that being
> slower. Even so, you'd think some kind of parallel processing
> arrangement could hide some of that...
TRIM is the keyword. Pages are erased during idle time of the disk.
The transfer speeds come from the Addressing delays and acrual write and read
timing constraints. Yes, silicon memory does have a finite bandwidth.
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Invisible <voi### [at] devnull> wrote:
> On 08/03/2012 03:23 PM, clipka wrote:
>
> > Last not least, there's also the question of cost: Using cutting-edge
> > technology for memory ICs would result in prohibitively high per-bit
> > costs; such production lines are therefore almost exclusively used for
> > high-margin products such as high-performance CPUs or GPUs, until the
> > next generation of cutting-edge fab technology becomes available. The
> > older production lines might then be used for another generation to
> > manufacture low-cost CPUs and GPUs, and finally for stuff where
> > per-transistor costs are more important than die size, such as memory ICs.
>
> Right. So that's why, even though 40nm technology already exists, they
> don't use it just to build (say) USB flash drives. (?)
They use 25nm chips for SSDs nowadays.
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"Aydan" <hes### [at] hendrik-sachsenet> wrote:
> Invisible <voi### [at] devnull> wrote:
> > On 08/03/2012 02:50 PM, Aydan wrote:
> > > Well I have two SSDs and I'm not a performace freak.
> >
> > You clearly have a hell of a lot more money than I'll ever have.
> >
> > Or rather, you /had/ a lot of money... ;-)
> >
>
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On 3/8/2012 1:31, Invisible wrote:
> Today's cars have
> performance within a few percent of cars made 40 years ago.
Uh, what? 40 years ago, 12MPG was a decent mileage, and you changed the oil
every 3000 miles or so, and added oil in between. 40 years ago, cars didn't
even have six digits on the odometer, because almost none of them lasted
100,000 miles. Electric windows and stereo radios were luxuries.
--
Darren New, San Diego CA, USA (PST)
People tell me I am the counter-example.
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