home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Fresh Fish 9
/
FreshFishVol9-CD2.bin
/
bbs
/
reviews
/
accelerators.lha
/
accelerators
/
SolidStateLeisureA5000020
< prev
next >
Wrap
Internet Message Format
|
1992-05-06
|
13KB
From: Barry McConnell <BMCCNNLL@vax1.tcd.ie>
Organization: The Amiga Online Review Column - ed. Jason L. Tibbitts III
Subject: REVIEW: Solid State Leisure A5000-16 68020 Accelerator
Keywords: hardware, accelerator, 68020
Path: menudo.uh.edu
Distribution: world
Newsgroups: comp.sys.amiga.reviews
Followup-To: comp.sys.amiga.hardware
Reply-To: Barry McConnell <BMCCNNLL@vax1.tcd.ie>
[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 th