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Travis Keller · Sep 12, 2005, 07:19 PM

What if osX Booted off a 6 gig 1" drive and the rest of the system ran on a 7,200 rpm 2.5" drive? Would it run faster performing multiple tasks? I know a 1" drive is slow but what if osX booted off a fast reading Compact flash card? Just a thought. Could you run multiple operating systems off a CF card when the switch to Mactel is complete? Just Brain storming at work

Andy8 · Sep 12, 2005, 07:59 PM

What RPM is the 6GB 1" drive spinning at? Why not just boot from the 7,200RPM 2.5" drive? That is plenty fast enough.
The Compact flash card needs to read/write at a decent speed, while it may seem to read fast, it will write very slow and make any OS painfully slow.
External drives are now very cheap and fast, I use a 250GB Lacie firewire 800/400 drive, which is very fast, quiet and cool to boot from.

Travis Keller · Sep 12, 2005, 08:11 PM

No, I mean booting the OS off a flash drive so the harddrive can concentrate on other tasks. Or booting multiple OS's off different flash cards/sticks holding the os. It would be as fast as waking up from a sleep when your computer boots becaus of the faster read speed.

Andy8 · Sep 12, 2005, 08:22 PM

Originally Posted by Travis Keller

No, I mean booting the OS off a flash drive so the harddrive can concentrate on other tasks. Or booting multiple OS's off different flash cards/sticks holding the os. It would be as fast as waking up from a sleep when your computer boots becaus of the faster read speed.

Your missing the point, Flash drives may seem to read fast, but they Write very slowly, your need decent read/write speeds to boot from, regardless of what "other" tasks your other drives are doing (not much at the same time if your booting off another drive). Instead of wasting time with CF cards, just get a decent size external firewire drive and divide it into multiple partitions and then stack as many OS's as you like onto one disk, that way, it boots the same speed, reading AND writing regardless. For the money you spend on CF flash cards you can buy lots of very nice external firewire storage.

Eriamjh · Sep 13, 2005, 07:38 AM

Originally Posted by Travis Keller

What if osX Booted off a 6 gig 1" drive and the rest of the system ran on a 7,200 rpm 2.5" drive? Would it run faster performing multiple tasks? I know a 1" drive is slow but what if osX booted off a fast reading Compact flash card? Just a thought. Could you run multiple operating systems off a CF card when the switch to Mactel is complete? Just Brain storming at work

I think the answer is no.

bighead · Sep 13, 2005, 12:14 PM

Jeez, now I'm curious about installing OS X onto a CF card in the PC Card bay. Anyone willing to donate a 2GB or 4GB card for testing? I'll give it back. I promise.

Travis Keller · Sep 13, 2005, 07:38 PM

I knew I was't crazy!

It should work.

Al G · Sep 13, 2005, 10:16 PM

If you think this is a good idea then you haven't actually tried it. The PCMCIA card slot on a Powerbook is dreadfully slow with any Compact Flash card, not to mention it inflicts a huge load on the CPU. Apple's implementation is partly to blame and the typical CF adapter being only 16-bit is partly to blame.

If you get a special 32-bit Cardbus CF to PCMCIA adapter from either Lexar or Delkin, it is a lot faster and doesn't peg the CPU but a decent 2.5" hard drive is still going to perform a lot better than flash ram.

And have you priced any 4GB CF cards lately? They cost more than a 100GB 5400RPM 2.5" hard drive.

Tesseract · Sep 13, 2005, 10:39 PM

Firewire hard disk.
Duct tape.
Enough said.

Travis Keller · Sep 13, 2005, 11:21 PM

The point isn't speed it is protibility. I just wanted to know if it can be done and if so how to do it.

Tesseract · Sep 13, 2005, 11:33 PM

How does having two drive instead of one increase portability?
Anyway, if speed is not important you could use a CompactFlash drive in the card slot, as others have suggested.

CanadaRAM · 11:49 PM

Originally Posted by Travis Keller

The point isn't speed it is protibility. I just wanted to know if it can be done and if so how to do it.

Well, the IS a lot to be said for protting...

Seriously, it's a bad idea. Flash is way too slow. Remember that the OS writes swap files to the boot drive CONSTANTLY.

Also, Flash memory is NOT made to be rewritten indefinitely; after enough writes it will die. Not an issue for a camera that is writing once or twice a day to a given location, but a real problem for an OS that will write thousands or tens of thousands of times a day.

http://www.pctechguide.com/03memory_Flash_memory.htm
"there are a number of reasons why flash memory is not a viable replacement for either [RAM or HD]. Because of its design, flash memory must be erased in blocks of data rather than single bytes like RAM. This, together with its significantly higher cost and the fact that memory cells in a flash chip have a limited lifespan of around 100,000 write cycles, make it an inappropriate alternative to RAM for use as a PC's main memory. Whilst electronic "flash drives" are smaller, faster, consume less energy and are capable of withstanding shocks up to 2000 Gs - equivalent to a 10 foot drop onto concrete - without losing data, their limited capacity make them an inappropriate alternative to a PC's hard disk drive. Even if capacity were not a problem, as with RAM, flash memory cannot compete with hard disks in price."

(Note: This is one reason you have a 3 - 5 year warranty on Flash cards, and Lifetime on RAM modules).

Now if you could put together a drive made of 6 Gb of DDR or DDR-2 memory, with a battery to keept the RAM alive and a controller that mimics a hard drive, and hook that via a 32-bit PCMCIA interface --- well, it would suck battery power like a good thing (probably would exceed PCMCIA or USB power limits) and you could fry eggs on it, but it WOULD be fast. Some companies have niche products to do this, but they cost kilobucks.

Thanks
Trevor
CanadaRAM

Travis Keller · Sep 14, 2005, 01:05 AM

How about a 1" harddrive? That would work decently because it can fit in a type 2 CF cardslot. Wouldn't it be nice to bring your WHOLE computer account with you no matter what Mac you were at?

cteselle · Sep 14, 2005, 01:16 PM

Originally Posted by Travis Keller

How about a 1" harddrive? That would work decently because it can fit in a type 2 CF cardslot. Wouldn't it be nice to bring your WHOLE computer account with you no matter what Mac you were at?

Get an ipod then. Done.

bighead · Sep 14, 2005, 01:36 PM

Originally Posted by CanadaRAM

Well, the IS a lot to be said for protting...

Seriously, it's a bad idea. Flash is way too slow. Remember that the OS writes swap files to the boot drive CONSTANTLY.

I understood the performance issues involved and that it isn't a great idea. However, back in 2002, I bought a PM9500 and set it up with a 2x120GB RAID1 and a G3 upgrade running Jagwire. Again, I wasn't thinking of it being a good idea, or being best value for the dollar. I was thinking about being able to do something kinda fun just for the sake of doing it.