Dan Knight
- 2007.05.25
Running OS X from Compact Flash
John Muir writes:
Hi Dan,
Just read your article about running from a Compact Flash card
via an IDE adapter. I have a little I could add to your report.
Since last October, I've been running my 12" PowerBook G4 (original 867 MHz model
with 640 MB RAM) from an 8 GB CF card in just such an adapter
I bought some months before. I'm currently right up to date with
OS X 10.4.9 and still have a few gigs free besides having
Office 2004 installed and my usual other apps. I'd call the
experiment a success, as this is my main machine a lot of the time
and has been used daily over that period, but as you found yourself
often it's getting there which is the tricky part. If you'd like to
hear the full story, I could mail you back on it; it's easily
enough for the OS X inclined.
A quick hint: FireWire target disk mode. It's great when you
have it and lets me "sand box" on an external drive when trying new
things out.
All in all I'm happy with my setup. The silence is truly golden.
Eventually I'd like to up the flash card - because as you
discovered yourself cards can be "idiosyncratic" shall we say - and
Leopard seems the best excuse for that. Apple didn't make these 12"
PowerBooks with hard drive replacement in mind, so it's a task I'm
well prepared to let wait!
John
Hi John,
Thanks for the good news about running OS X from
flash. I assumed it would work, and I'm glad to hear from someone
doing it successfully. Does the PowerBook feel as responsive
running from Compact Flash as it did with a hard drive? My PB 1400
seems to wake up faster from sleep when running from flash; how
about your 12" PB G4?
I imagine it took some work to trim OS X and your
application library to fit on an 8 GB card with room for
Office 2004 and work files. If you'd like to share that story, I'd
be happy to publish it.
Dan
Running Old PowerBooks from Flash Is Very
Tempting
Andrew Main writes:
Dan,
Thanks for this article. For over a decade I've been hoping to
see flash memory replace noisy (though that problem's mostly been
solved in recent years), unreliable (moving parts wear out) hard
disks. Maybe it won't be too long now before flash prices reach
rough parity with disks.
I also have a PB 1400 (with a 250
MHz G3 CPU); it was one of the all-time greats, and I keep it
around as a Mac OS 8.6/7.6 machine. It has a 2 GB drive in it
now; a flash replacement for under $50 is very attractive. And my
'Pismo' PB, which I keep for Mac
OS 9 & 10.3 (and to play with Linux) could do nicely with
a 16 GB flash drive to replace the 20 GB in it now.
I note Addonics also offers
an SATA version of their 2.5" adapter card; I just bought a 160
GB disk for my MacBook Pro for ~ $100, but I'd pay $200 for a 256
GB flash memory card to replace it.
As for older Mac notebooks that use SCSI disks, there may be a
possible solution: In the waning days of the SCSI era, Apple was
offering replacement 1 GB disks that were actually IDE/ATA
disks with an ATA-to-SCSI adapter card attached. I've used one of
these to make a 2 GB ATA disk usable as a SCSI drive, and it
might work with one of the Addonics adapters. Maybe I'll give it a
try when I get around to assembling a PB
180c (another all-time favorite) from the boxes of parts in the
corner.
There might also be ATA-to-SCSI adapters for full-size 3.5"
disks; I seem to have a dim memory of seeing something like that
once. I note Addonics also makes some 3.5" flash to ATA
adapters, so there might even be hope for your Mac Plus - or the accelerated (16 MHz!)
LC I plan to put together for System 6 (fast and stable -
remember?).
Andrew
Andrew,
First off, I'm jealous of your G3 upgrade. I'd
like to acquire one someday for my 1400, and also do some hardware
transplants. I have a 133 MHz one with 64 MB of RAM and an internal
ethernet card, and I have a 166 MHz one with the superior display.
Combined with a G3 upgrade and a WiFi card, it could be a great
machine for the classic Mac OS.
I'm updating my review with a link to the SATA
adapter, which unfortunately only holds a single CF card. Still a
cool device!
I like your thinking. I'd love to have a flash
drive for my accelerated Mac Plus, but fiddling with a CF card and
some adapters isn't tempting at all. I'll wait for someone else to
figure it out first. (And I'd be happy to publish their results
here on Low End Mac.)
If you find a source of those ATA-to-SCSI adapters
for notebook drives, be sure to let me know.
Dan
Testing a Compact Flash Hard Drive
Lee Kilpatrick says:
I enjoyed reading the review of the Addonics CF adaptor for a
hard drive replacement, but I was wondering if you tried it in your
Power Mac G4? The 1400 is, as you pointed out, not a very modern
machine, so maybe the speed was limited by the machine itself, and
the G4 would give a better idea of how a flash drive might perform
on a more current system. Not sure what speed the ATA bus is in
your G4, but it seems like it would almost surely be faster than
the 1400.
Lee
Lee,
Thanks for the suggestion, but there are two
reasons I didn't try it. First, 2.5" IDE hard drives don't use the
same connector as 3.5" hard drives, and I don't have the
appropriate adapter. Second, it's a royal pain taking my Power Mac
G4 out of my desk and then putting it back in place and getting
everything plugged into the right ports (I have some USB 1.1
devices on the internal ports, USB 2.0 on a pair of add-in cards).
Besides, it's my production machine, and I'd rather not experiment
on it.
I really should pick up a nice Lombard or Pismo
some day, as either would make a better testbed for notebook
upgrades and allow me to run both the classic Mac OS and OS X.
I also have some older G3 and G4 Power Macs I could use as a
testbed. I'll check with Addonics about the appropriate
adapter.
Dan
More to CPU Upgrades than Clock Speed
Glenn Dawes writes:
Hey Dan,
Very nice piece on the MDD
upgrades. However, it is old news, but it is nice to have it
collected as you have. I have been seriously considering upgrade
options for the CPU on my single 1.25 MDD for 2 years now, and I
remember when Giga first introduced their upgrades as either 1.25
dual or 1.42 dual. The 1.42 was unstable and hard to get two 7455B
to work at 1.42. 1.33 seemed to be a sweet spot, and I suspect they
discontinued the dual 1.25 as a result. But my recollection is that
the Giga 1.33 is an overclocked 1.25 setup, which shouldn't be a
problem, but nice to know. This upgrade is plug and play, since the
chipset is the same from stock.
The Sonnet upgrades are new and only about 2-4 months old. They
use the 7447A chipset which will require a ROM update to run in any
MDD, since the MDD only recognizes the 7455B chipset - also not a
problem, since Sonnet provides the software ROM update. This is not
plug and play. Also the Sonnet chips have no L3 cache and a 512K
L2. All things considered, my discussions with a Sonnet tech
indicates that a dual 1.25 stock with 1 MB L3 is very very
slightly slower than a dual 1.6 7447A with 512k L2, and the 1.8 is
marginally faster overall because of the 1.8, however without the
L3 there is some serious bottleneck slow down with the slow 167 MHz
[system bus] (say compared to a G5).
Further, Chris Seitz is not entirely correct on the space
limitations for a CPU upgrade in a MDD tower. There is plenty of
room, and the small size of the heat sink on the Sonnet upgrade has
to do with the upgrade being designed to work in an Xserve, which
if you remember is very flat. The MDD is roomy, which is why the
Giga upgrade has not only a taller heat sink but a large fan on top
of that. The Giga upgrade will only work in MDD Macs where
there is room, but it will not work in an Xserve, which is based on
the same architecture as the MDD (actually vice versa - the MDD is
based on the Xserve, but as a tower, not a stackable flat server).
You might want to correct that in your article . . .
there is room in the MDD . . . lots, and the limitation
for upgrades is more about the stability of the architecture rather
than absolute space.
That said, if you would like a script of the discussion I had
with a Sonnet rep about their upgrades and there performance over a
stock 1.25, I can send that to you to publish for your readers. I
found it useful, and they might as well. Just let me know if you
are interested, and I'll email you the text - it's about 2 pages of
detailed information organized as questions followed by
answers.
My interpretation from the conversation is the Giga upgrade is a
better deal, plug and play, and probably a faster upgrade overall
than a 7447 based upgrade. Basically the dual 1.6 Sonnet is
equivalent to a dual 1.25 stock, and the 1.8 is about the same as a
dual 1.42 stock. So the $499 for the dual Giga 1.33 is right about
in the middle for performance, is plug and play without a ROM
update to recognize the 7447 chipset, and is faster than the $499
1.6 from Sonnet. All upgrades are duals.
If I were to recommend one or the other upgrade for an MDD
owner, I would easily recommend the Giga overall, despite the very
slight overclock. The Sonnet 7447 are too expensive for basically
the same performance and are not plug and play exactly. Both are
good but I would prefer the Giga.
Glenn
Glenn,
Thanks for sharing your findings. I have no way of
determining how much space there is inside my Power Mac G4 when
it's closed, but I know the stock CPU module has a pretty large
heatsink attached.
It's hard to project how two different upgrades
will perform in the same computer. The Giga is a slower CPU with a
smaller L2 cache, but it has a large (2 MB per CPU) L3 cache.
The Sonnet upgrades clock faster and have a larger L2 cache, a
different revision of the G4 CPU, and no L3 cache. I haven't been
able to locate any benchmark results that would allow me to compare
the two.
The Giga has twice as large a L3 cache as Apple's
CPUs, so it would probably hold its own against Apple's 1.42 GHz
model. Without a L3 cache, the 1.6 GHz Sonnet could well be slower
than the stock 1.42 or Giga's 1.33. Let's hope Bare Feats or
someone else has the opportunity to test them.
It's not much of a concern whether an upgrade
requires a ROM update, and since speeds are likely to be similar,
I'd lean toward the Sonnet 1.6 GHz at $50 less, but there are
probably equally valid reasons (L3 cache, for instance) for
choosing the Giga Designs upgrade.
Dan
G4 Upgrade Questions
Kate writes:
Dear Dan,
After my last emails, I did
decide to upgrade my G4 400 MHz
Sawtooth. I am adding more RAM and I am looking at Processors.
One of the games I have and want to play (Myst V) recommends 1.6
GHz. I have been looking at the
Sonnet both in the 1.6 and the 1.8 and then saw the Newer Tech
MAXpowr 1.8, which says that it is faster than the others
because instead of a 7447, it is a 7448. Whatever that means. It is
also $100 more.
My thought is that if it's that much faster, why don't they say
it's a 2.0? What is a good choice, and are there ratings for this
processor, at least I haven't been able to find any. Next question.
In one of your articles you said something about the RAM slowing
everything down. Is there a limit to what the processor can do
because of the speed of the RAM? And to piggyback on that. It seems
that somewhere I read that I could use either the PC100 or PC133
memory sticks, in fact I think I have some PC133 in my machine.
Thanks a ton, I love my Mac and love making it last.
Kate
Kate,
There are several different factors that determine
how much computing power a CPU has. There's raw clock speed, like
1.8 GHz, which only tells us how fast it can handle data after it's
acquired it. Then there are the caches, which act as high speed
buffers between main system memory (100 MHz to 167 MHz on G4 Power
Macs) and the CPU itself (350 MHz to 2.0 GHz).
The "level 2" (L2) cache is the one closest to the
CPU (level 1 is in the CPU itself), and on modern G4s, it runs at
the same clock speed as the CPU. The 7447 has a 512 MB L2 cache,
while the 7448 has a 1 MB L2 cache. That's twice as big, which
means two times as much data is available to the CPU immediately.
(Some G4s, such as the PowerPC 7455, only have a 256 MB L2 cache.
However, it also supports a level 3 cache, which acts as a large
buffer between system memory and the L2 cache.)
To answer your question, "if it's that much
faster, why don't they say it's a 2.0?" That's because a CPU's
clock speed is an absolute measurement. It doesn't measure
performance; it only tells how many times per second the CPU can do
something.
In general, the more times per second it can
perform a calculation, the better, but the other factor is that it
must have data and instructions to work with. If that information
isn't in the L1 cache, it has to call for it from the L2 or L3
cache - or even system memory. Each step further away from the L1
cache means a longer delay in waiting for that data to reach the
CPU. And while it's starved for data, it's wasting those cycles
doing nothing at all.
That's why the caches are so important. The faster
the cache, the more quickly the CPU can acquire data from it. The
larger the cache, the more data you'll have for the CPU to acquire
quickly. Of course, there's a downside to this - otherwise we'd
have CPUs with 1 GB L2 caches. It takes a lot of circuitry to
double the size of a cache, which increases chip size and cost.
That's why every CPU is a compromise of bus speed, core speed, and
cache size.
In the end, the 7448 was the pinnacle of G4 design
when it comes to the size of the L2 cache. All else being equal
(which isn't always the case), a 7448 running at the same speed as
a 7447 or 7455 will provide the best performance.
That said, there are other factors at play. While
Ubisoft says a 1 GHz G4 and 32 MB of video memory is a minimum
requirement for Myst V, Inside
Mac Games notes that "users with stock 1.6 GHz G5 desktops have
had to turn the game down to low settings to achieve playable
performance." The reviewer then goes on to recommend a minimum of a
1.42 GHz G4 and 128 MB of video memory on your graphics card.
Between spending $450-600 for a CPU upgrade and
$120-150 for a Radeon 9200, you might want to investigate the
performance potential of the $599 Mac mini with its 1.66 GHz Intel
Core Duo CPU ($519 refurbished from
the Apple Store, when available).
Dan
USB Adapter for a PCI Power Mac
Dear Mr. Knight,
I have a Power Mac 7200 which uses
a serial port for the printer connection. Could you please tell me
if an adapter is made which would convert the serial port to a USB
connection so that I could use a new printer. If such an adapter is
made, where can I obtain one?
Thank you.
Leo Comrie
Galesburg, MI
Hi neighbor (we're about an hour away in Grand
Rapids, MI),
I don't know of an adapter that will convert the
Mac's serial port to USB, but there's a simpler solution. Your
Power Mac has PCI expansion slots, and there are USB cards that
plug into PCI slots that will work with Macs. They generally
require Mac OS 8.1 or later, which should run nicely on your 7200.
A Google search for "usb pci mac" should give you some good
leads.
Dan
No Tiger Drivers for Many Lexmark Printers
Responding to advice offered in Getting a Dell Printer to Work with a
Mac, John Hatchett writes:
Dan
Thanks for the tip! However, Lexmark doesn't seem to have a lot
of printers that have "Tiger" drivers. Still, I need to go home and
make a visual inspection to see if I can match my printer up to the
Lexmark printer. I can try and access it through the built Lexmark
Printer sharing function of Tiger.
What do you do with a PowerBook
180?
My boss found one lurking around a science room - and it still
works! For a while it hung around the eMac lab, and then I had an
inspiring thought. Students signed in and out of the writing center
all day, and I spent a lot of my time attempting to enter their
handwritten entries into a spreadsheet. (The lack of neat
penmanship in current high school students is appalling. I could go
on about their inability to read an analog clock, but....)
Eureka! I thought, make the students use the PowerBook 180 to
log in and out electronically! The PowerBook runs OS 7.5, and it
has a floppy drive. As soon as can install AppleWorks in my new
Intel iMac, I should be able to translate the file to something
more usable.
There is nothing like using old technology to solve new
problems.
John Hatchett
John,
Congratulations on finding a great new use for old
technology. System 7.5.3 and the 7.5.5 update are free downloads
from Apple, and older versions of ClarisWorks should run just fine,
allowing you to use a spreadsheet or database for your
information.
Sorry to hear that Lexmark is deficient in Tiger
support, as that version of the Mac OS has been current for two
years now.
Dan
Dan Knight has been publishing Low
End Mac since April 1997. Mailbag columns come from email responses to his Mac Musings, Mac Daniel, Online Tech Journal, and other columns on the site.
