dennisg@sdcrdcf.UUCP (Dennis E. Griesser) (04/23/85)
Perhaps you have seen advertisements for the megabyte Mac expansion offered
by Micrographic Images. I have had a beta-test version for awhile, and would
like to offer my comments.
WHO MAKES IT?
The board was designed by Spies Labs, a manufacturer of Apple and IBM add-in
cards. The system is sold by Micrographic Images, but only through computer
dealers.
INSTALLATION
The unit is a single piggyback board. It is as wide as the Mac logic board, but
only extends from the edge to a little past the RAM array. The unit carries a
complete 1Mbyte of 256K DRAMs. The original ram array is not used, although its
chips stay in place to simplify installation. Three chips must be de-soldered,
and a small number of connections made to the original board. A bolt is used to
fasten the piggyback on, although it gets a lot of support from headers that
extend from the add-on to the original board. The piggyback is made of a nice
heavy fiberglass, double-sided and solder-plated.
The piggyback approach takes most of what little room is left over the Mac logic
board. This makes the MegaMac incompatible with other piggyback upgrades, most
notably the Hyperdrive. I hear that they desolder the 68000 CPU and mount a
piggyback in its place {ugh}.
As a beta user, I was able to install the upgrade myself. It took me about 1.5
hours. Doubtless, you could slap one in inside of 20 minutes given the proper
tools and lots of practice.
Half of this time was spent desoldering the *#$#^$% three chips, and
cleaning up the PC around them. I was using a large hand-cocked solder pump and
a rather hot iron, but the 4-layer board in the Mac has dedicated power and
ground planes that act like good heat-sinks. Since I had no desire to ruin the
logic board, I chopped out the chips and removed the lead stubs one at a time.
After installation and testing, the power supply needed a minor adjustment. The
additional chips loaded the +5 down by about .2V. The adjustment is easy to do
and was not at all delicate. My beta unit had plastic RAM packages, made by
NEC. I have heard that commercial units will use low-power ceramic chips.
If I ever decide to get rid of my Mac, the megabyte can be removed. You can go
back to a skinny Mac just by pulling a connector, replacing three chips, and re-
tweaking the power supply.
OPERATION
The expanded Mac worked the first time. With my 3-month old Mac on the line,
I was justifiably paranoid! It has been very reliable since then. It does
not run noticibly hotter, although I will probably add a fan just in case.
I didn't get a lot of software with it, and no written instructions. What I
got was the equivalent of a Fat Mac (512K), plus a large (512K) RAM disk.
This means that you can run Switcher, and other applications that take 512K.
It also means MacPaint does not whack the disk when you show_page or move the
window around. MacWrite will now accept huge documents. Starting and exiting
an application is pleasantly speedy. The RAMdisk is comfortably larger than a
physical Mac disk and doesn't take away from your Fat area.
The RAM-disk supplied with my unit was crude. When the Mac booted, it would
end up with both the boot-disk and RAMdisk on the desk top. Then you use the
Finder to copy the system folder and applications to the RAMdisk and eject the
boot-disk. I have been told that commercial units will come with a much better
RAMdisk.
COST
The first flyer I saw for the MegaMac mentioned a price of $1600, installed.
The price has since dropped a bit ($1400 sounds familiar). It's a bit cheaper
if you already have a Fat Mac. This is just a marketing stunt since any
original RAMs in the Mac are unused, and they have to add the full 1M anyway.
An upgrade is under consideration that will use the original RAM, giving Fat
Mac owners 1.5M.
This is obviously a lot of money! In fact, it's about twice what Apple wants
for a 512K upgrade. It kinda makes sense, in that you get twice as much memory
for twice as much memory. BUT Apple's price is just too steep. It makes a poor
baseline to set other prices by.
DO YOU NEED ONE?
It took me no time at all to get fed up with the slow disks and the way Mac
always was hitting them up for something. The MegaMac has freed me from this
and is a reliable and real product. The software is not fancy, but it is
usable and better is promised.
A MegaMac with two disk drives makes a nice system. At this rate, I won't
be thinking about a hard disk for a couple of years.
The steep price is certainly a negative factor. Another is that the upgrade
must be performed by a dealer. I have heard several reasons for this, but none
seem very convincing.
[disclaimer: I know the folks at Spies Labs, and have visited Micrographic
Images once. I have tried to be fair in this review, but some bias might have
crept in. These opinions are mine, and not necessarily those of the company
I work for, SDC. I know of no connection between SDC and the MegaMac folks.]