esata with PCMCIA card vs USB 2.0...??

  • Thread starter Thread starter hizark21
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Timothy said:
One advantage of eSATA hard drives is that they can be
used to hold the OS if your PC can boot from an eSATA drive.
I've only seen that capability listed for desktops, though - not laptops.
Neither have I heard of a laptop that could boot from a SATA
or eSATA drive on a PCMCIA card. This makes eSATA on
a laptop good only for holding data - just like USB. The other
advantage of eSATA still holds for a laptop, though, and that's a
speed-of-data-transfer advantage over USB.
Click to expand...


What sort of throughput are you getting on eSATA on a laptop? A friend
of mine just got himself an eSATA PCCARD, and the same drive that used
to get 25-26 MB/s on USB is just barely faster in eSATA at 28-30 MB/s.
Was expecting a bigger boost from it.

Yousuf Khan
 
A PCMCIA bus only has a bandwidth of 20mbps. But a ExpressCard slot
bus has and bandwidth of 2.5 Ggbit/sec. Super USB 3.0 will support 4.8
gbps (http://gizmodo.com/5084086/super+speed-usb-30-formal-unveiling-
next-week-windows-7-wont-support-natively ) whenever it comes out.
Click to expand...

I'm being a little imprecise with my terminology here. I do believe
that the card he has is an ExpressCard rather than the older PCMCIA or
PCCard forms. It's a long narrow card rather than the short wide cards
of the olden days.

Yousuf Khan
 
I was being "imprecise", too. What I have is really an ExpressCard.
Here is the SIIG webpage on it:http://siig.com/ViewProduct.aspx?pn=SC-SAE512-S1
The specs say "Supports data transfer rate up to 3.0Gb/s (300MB/s)",
but I've never measured it. I've had it for about 10 months, now, and
it has worked flawlessly. I'm still disappointed that I can't boot with it,
though.
Click to expand...

Does your laptop BIOS have the ability to boot from SCSI devices? I'm
pretty sure that this card shows up as a SCSI device under Windows.

Yousuf Khan
 
Can someone recommend a esata expresscard that can boot a external
HD...? The PPA esata expresscard that Frys carries is bootable. The
problem is that PPA's support seems to be poor.
 
Can someone recommend a esata expresscard that can boot a external
HD...? The PPA esata expresscard that Frys carries is bootable. The
problem is that PPA's support seems to be poor.
Click to expand...

The eSATA ExpressCard would probably need its own extender BIOS that
supplements the system BIOS for you to be able to boot from it.

The eSATA connections on desktops are just converter cables from their
onboard SATA ports, so they don't need anything special to boot from
them, they just look like any other SATA drive.

Yousuf Khan
 
"?" on the SCSI device booting. All I know is that Dell's User Manual
states that ExpressCards are not bootable devices, and SIIG technical
support says that its eSATA ExpressCard can't be used to boot a laptop.
The ExpressCard doesn't even show up in any hardware list until the OS
has started up. A few of Dell's latest desktops have eSATA controller
ports, though, and they can boot from an external eSATA hard drive.
Click to expand...

Which would probably explain why my friend is complaining about the
laptop boot times slowing down tremendously when he has the external
drive connected via eSATA rather than USB. If the eSATA Expresscard
doesn't even show up until the OS has booted, it's probably taking
that extra boot time just to enumerate the Expresscard device. It
seems on balance, eSATA is not worth it on a laptop.

Yousuf Khan
 
Timothy said:
I haven't noticed an extension of boot time that depends on whether the
eSATA ExpressCard is plugged in or not. It could be, but it's not
noticeable. In any event, it would only happen when it's plugged in. But
why would device "enumeration" take more time if it occurred after rather
than before OS startup?
Click to expand...


My guess is that if it's already enumerated by the BIOS, then the BIOS
just passes along its information directly to the OS through Plug'n'Play
protocols, whereas the OS would have to go through all of the detection
procedures itself if the BIOS didn't pass it along. Besides, his OS is
Vista, it doesn't take much to extend its boot time by another couple of
hours. XP seems to be a lot faster at boot-up than Vista.

Yousuf Khan
 
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