Subject: REVIEW: Solid State Leisure A5000-16 68020 Accelerator
From: Barry McConnell <[email-masked]>
Newsgroups: comp.sys.amiga.reviews

[The Solid State Leisure A5000-16 is an affordable 68020 accelerator with
many of the standard features such as 32 bit expansion RAM and 68000
fallback mode.  It does have its quirks and shortcomings, though. JLT3]

[This review previously appeared in comp.sys.amiga.[hardware,misc], but I'm
reposting it here for the sake of those who are interested but don't follow
those groups.  JLT3]

Here is a review of Solid State Leisure's A5000-16 68020 accelerator board,
which I got for my Amiga 500 a week ago. Before I start, I just want to
mention that I had to wait almost ten weeks for it to arrive, and
telephoned them (long-distance) seven times during that period. What
happened was that they sent out one board by registered post, which never
got to me. Since it was insured, they sent me out a second one, as they
would be able to claim compensation for the first one. The second one never
got to me either. In actual fact, both were eventually sent back to SSL by
Irish Customs (I live in Ireland; SSL are in England, which is the country
next-door to us; look at a map...), who for some unknown reason, refused to
send it on to me. I can only assume that SSL made a mess of the Customs
declaration docket on the parcel, as I have received a lot of other goods
from England in the past, including a hard drive, with no problems at all.
Anyway, they finally sent the third board out by courier, which did get to
me.

The hardware:
-------------
 
16.67Mhz 68020, with space for 4Mb of 32-bit RAM (comes with 1Mb as
standard, uses 256*4 80ns DRAMs, which is handy if you have some in your
A590/A2091), space for a 68881/2 maths coprocessor, but no MMU. All this
sits on one small board, which plugs into the 68000 socket in your
A500/A2000. The original 68000 chip fits onto the accelerator board, and is
used in the 68000 fallback mode.  You don't need a new PSU to use this
board, even if it means you'll end up with 5Mb inside your Amiga, as the
extra RAM chips take a minimal amount of power.
 
There is an option to copy your Kickstart ROM into fast 32-bit RAM, and the
board will automatically remap all the Amiga's ROM accesses into RAM, so
anything which relies on the OS routines (including windows) will run much
faster. This currently only works with 1.2/1.3 Kickstart ROMs, but an
update to the software supplied will support KS2.0, and will be available
soon.
 
The memory is *not* autoconfig; you must run an AllocMem program in your
Startup-Sequence, which searches for 32-bit memory, and adds any found to
the system's memory list.

Installation:
-------------
 
Probably not for those who don't feel confident about ripping chips out of
their Amiga (I got a friend to do it for me). The first time we switched on
with the '020 installed, the screen went a worrying shade of green, but
this was probably because the board wasn't properly seated in the socket.
(As an aside, ever wanted to know what happens when you turn your Amiga on
with no 680x0 chip at all? - Absolutely nothing! (You see a grey screen.)
8-) )
 
I was able to use some of the RAM chips from my A590, and these go into the
4 1Mb banks on the board, so you can have from 1-4Mb of 32-bit RAM. (I have
a total of 3Mb of 32-bit RAM, 1Mb of 16-bit fast RAM, and 1Mb of chip RAM,
giving 5Mb altogether.)

Speed:
------
 
SSL claimed a 500% (5 times) speed increase, and true enough, most
benchmarks will give this. Mips gives a result of 4.969519 (as opposed to
0.847750) which is almost six times faster. AmigaBench gives a result of
3561 Dhrystones/sec (as opposed to 1012), but the optimised 68020 version
gives 5694. The various benchmark programs included with the board (CalcPi,
Ronin CPU speed, Whetstone, another version of Mips) give 4-5x speed
increases.
 
However, benchmarks like these are not what it's all about, so I did some
"real-world" tests, as these are the ones you will find useful/interesting:

                                             68000   68020   Speed increase

Time to LhArc DPaint to RAM:                 3m00s   1m06s   2.7
Time to un-LhArc it                          1m09s   0m22s   3.1
Time to PowerPack a 200K file                1m53s   0m34s   3.3
Time to 'echo' a 400K sound sample in AM3    2m43s   0m50s   3.2
Time to decompress a disk using DMS          4m20s   1m26s   3.0
Time for HamSharp to convert a pic GIF->IFF  1m35s   0m30s   3.1
Time for TurboGif to display a GIF pic       11.2s   4.3s    2.6
Time to open a dozen windows on Workbench    26.7s   18.0s   1.4
Time to close them all                       29.1s   14.0s   2.0
Time to draw a Mandelbrot set                26.6s   5.9s    4.5

Oi! Where's my DMA gone??
-------------------------
 
There is one serious problem with the board: you can't DMA from your hard
drive into its 32-bit memory. There has been some discussion of this
problem on Usenet, and apparently while the FileSystem manages to get
around it, it doesn't do it very well. Just to show what I'm talking about,
here are the results from DiskPerf2, running first in normal 68000 mode
(DMA-ing into ordinary 16-bit fast RAM), then in 68020 mode (failing to DMA
into 32-bit RAM, so it reads 512 bytes at a time into 16-bit RAM, then CPU
copies them up to 32-bit RAM). My hard drive is a Quantum LP52S - a very
fast SCSI HD - in an A590.

DiskPerf2.   Testing Files:
 
Create Files:    23 files/sec.	  Directory Scan:   117 entries/sec.
Delete Files:    62 files/sec.	  Seek/Read Test:    94 seek/sec.
 
Read/Write Speed Test:  (bytes/sec.)
 
Buffer:  512     Read:     30,169     Write:     22,036
Buffer:   4k     Read:    221,405     Write:    169,892
Buffer:   8k     Read:    325,644     Write:    255,252
Buffer:  32k     Read:    382,691     Write:    445,823
Buffer:  64k     Read:    476,625     Write:    562,540
Buffer: 256k     Read:    576,140     Write:    695,342
 
(Note: This was on a slightly fragmented partition; I sometimes obtain
speeds of up to 800-850K/sec.)

DiskPerf2.   Testing Files:
 
Create Files:    15 files/sec.	  Directory Scan:   125 entries/sec.
Delete Files:    61 files/sec.	  Seek/Read Test:    80 seek/sec.
 
Read/Write Speed Test:  (bytes/sec.)
 
Buffer:  512     Read:     26,211     Write:     19,772
Buffer:   4k     Read:     39,954     Write:     29,049
Buffer:   8k     Read:     40,398     Write:     29,293
Buffer:  32k     Read:     40,249     Write:     27,643
Buffer:  64k     Read:     39,991     Write:     27,902
Buffer: 256k     Read:     40,077     Write:     28,352

As can be seen, this problem occurs when manipulating large files; you
won't notice any difference when loading/saving small files, such as small
utilities, text files etc. But for large files, you're talking about a 3-6x
speed _decrease_. I copied about 600K of data (mostly one big file) from my
hard drive to RAM: before installing the 68020, and it took 6.9s. With the
68020, it took 21.7s. Copying from one partition to the other was twice as
bad: 8.5s for the 68000, 50s (!) for the 68020. Reading 2Mb sound samples
in AudioMaster is now a joke. For some operations, I have timed speeds of
as low as twice that of a floppy, cough, choke...
 
This problem is something which you can live with, as of course even the
worst cases are faster than floppy, and it won't affect you very much
unless you like messing around with large files, or frequently boot very
large applications (such as ProPage). But it is something to bear in mind
if you are considering purchasing this board. Before I ordered it, I asked
SSL about the DMA problem, and the man I was talking to told me it wouldn't
really affect me as long as I left some ordinary 16-bit fast RAM in the
A590 (which you can DMA into) as a buffer for the FileSystem to use. Hmm...
I think he was wrong! 8-(
 
Just as an aside: I ran DiskPerf on the RAM disk, and was suitably
impressed by the results. First 68000, then 68020 with its 32-bit RAM...

DiskPerf2.   Testing Ram Disk:
 
Create Files:    14 files/sec.	  Directory Scan:    15 entries/sec.
Delete Files:    28 files/sec.	  Seek/Read Test:   360 seek/sec.
 
Read/Write Speed Test:  (bytes/sec.)
 
Buffer:  512     Read:    212,606     Write:    174,066
Buffer:   4k     Read:    840,205     Write:    548,418
Buffer:   8k     Read:    967,321     Write:    599,871
Buffer:  32k     Read:  1,092,266     Write:    647,269
Buffer:  64k     Read:  1,106,092     Write:    658,653
Buffer: 256k     Read:  1,125,081     Write:    668,734

DiskPerf2.   Testing Ram Disk:
 
Create Files:    39 files/sec.	  Directory Scan:    47 entries/sec.
Delete Files:    80 files/sec.	  Seek/Read Test:   370 seek/sec.
 
Read/Write Speed Test:  (bytes/sec.)
 
Buffer:  512     Read:    255,750     Write:    224,438
Buffer:   4k     Read:  1,899,594     Write:    916,587
Buffer:   8k     Read:  2,702,515     Write:  1,078,781
Buffer:  32k     Read:  3,912,597     Write:  1,248,304
Buffer:  64k     Read:  3,912,597     Write:  1,337,469
Buffer: 256k     Read:  4,599,017     Write:  1,351,257

Compatibility:
--------------
 
Very good, actually. Almost all productivity software runs perfectly under
the '020. There seems to be only one problem with the board with respect to
compatibility: while it doesn't have an MMU, some software thinks that it
does, and promptly crashes when trying to find out more about it. A-MaxII
crashes because of this, as does Nic Wilson's SysInfo. Both crash with a
"Coprocessor Protocol Violation" error (GURU 8000000D). Another program
once told me I had a 68020 with a 68851 MMU, but has crashed every other
time I tried to run it.  This is quite worrying...
 
Another program which doesn't like the board is HD-Toolbox. When you boot
it, you are greeted by a requester telling you that some drives have been
added/removed from the system, and to click on "Save changes to drive" to
tell other drives about this. But on clicking the "Partition Drive" button
first, you see that all your partition data has been lost, and instead has
been reconfigured to the default 2 partitions (25Mb each in my case). Click
on "Save changes", and 0.5 seconds later, you are left with one very empty
hard drive!!  You don't even get an "Are you sure?" requester! Since the
program works with the A3000, I can only assume there is something wrong
with the 68020 board to upset HD-Toolbox in this way. (It works in 68000
fallback mode, though.)
 
IntuiTracker and EdPlayer don't like faster processors, and screw up the
music slightly, but ModuleMaster works fine, as it uses the new ProTracker
play-routines. Apart from that, everything else seems to work fine.
 
I can't say much about games, as I don't exactly have terribly many of
them.  Two I did try were R-Type2 and F-18 Interceptor. The former seems to
work fine with the added speed (it crashes on the A3000, though), and the
latter *blazes* along if you get it into 32-bit RAM. If you've ever seen it
on the A3000, you'll know what I'm talking about!
 
Many demos don't work on the '020. I tried a total of nine. The ones which
worked perfectly were Coma, Dreamscape, Mesmerized, Neutron Dance and
Phantasmagoria (although the scrolly message at the start of this was a bit
upset). The ones which didn't were Angels (starts out OK, then there are
slight glitches, then finally it crashes), Mental Hangover (crashes after a
while), Seven Sins (crashes fairly quickly) and Substance (lots of
glitches, although their fractal routine runs much faster...).
 
There is also a 68000 fallback mode. You operate this by clicking on an
icon, which reboots the machine using the 68000. Unfortunately, there
doesn't seem to be any way of getting out of this mode, other than turning
the machine off then on again! And this doesn't suit me at all, especially
with the hard drive attached: once I left it off for 15 seconds, turned it
on, and was greeted by a yellow screen, which wouldn't go away. (How long
*should* you wait after powering-down when you have a lot of memory
installed, and an expensive hard drive??) Also, the board's memory cannot
be accessed in fallback mode, as it is outside the 16Mb address space...

Hey, Mr Bank Manager...
-----------------------

Prices... A5000-16 ... 295
          B5000-25 ... 595       
          B5000-40 ... 1162

(The B5000 is a 68030-based board, 25Mhz or 40Mhz. All prices are in
Sterling pounds, and include 17.5% VAT, which you can take off if you're
outside Britain.)

Address:
    Solid State Leisure Ltd
    80 Finedon Road
    Irthlingborough, Northants
    NN9 5TZ, England.

Telephone: (International)
    +44 933 650677

They'll send you out an information pack on request. Feel free to e-mail me
if you've any questions...

Barry.
[email-masked]