From: davem@hp-lsd.COS.HP.COM (Dave K. Martin) Date: Mon, 13 May 1991 21:31:23 GMT Subject: Re: Need help to Lucas/Francis board Message-ID: <19620024@hp-lsd.COS.HP.COM> Organization: HP Logic Systems Division - Col Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!sdd.hp.com!hp-col!hpldola!hp-lsd!davem Newsgroups: comp.sys.amiga.hardware References: <13570@pasteur.Berkeley.EDU> Well, I can't comment on the Lucas/Francis combo (unless someone wants to make a donation to my 1000 upgrade project :-). You can pretty much plug a 68010 in with no problems. Look for MC68010 on Fred Fish 18 for a complete article on how to do so. It also includes the DeciGel software patch to trap illegal instructions. There is a much improved version of DeciGel on FF-454. I ran my A-2000 for a couple of years with a 68010 and the original DeciGel with no problems whatsoever with the exception of one game (which I never got the hang of playing anyway). Most things didn't seem to show much of an speed increase, a few math intensive routines were noticably faster though. Overall, I wouldn't recommend this as a major speedup hack. It is cheap though, about $15.00. The lust for power and speed finally overwhelmed common sense and I went and got a CSA Midgit-Racer. This would work either with my hard drive+controller or with my Microbotics 8-up board but not both. It also seemed to work ok with no expansion boards plugged in. In all cases, the net effect was about a 10-15% slowdown in all tasks. I guess the 7.14mhz 68020 was spending too much of its time pretending to be a 68000 to show any speed increases. The version I was using did not have a FPU chip installed. When I called CSA, they said the Midgit Racer was intended as a floating point accellerator rather than a general system accellerator and were being mis-represented by the sales persons. I was able to trade the Midgit Racer for a 25mhz Mega-Midit-Racer with a 68030 and provisions for 8 meg(more?) of 32 bit memory. So far, I don't have any 32 bit memory on the board but even so, it makes a noticable difference in just about everything that runs. Some things run as much as 1.5 times as fast, especially if I'm unarcing from ram to ram. I expect the speedup to be on the order of 2-2.5 times that of the stock 68000 once I get some 32 bit memory. There are a few demos and games that refuse to work with the 68030 but there are both software and hardware switches to reboot into 68000 mode (the 68000 is removed from its socket, the MMR plugs into it, then the 68000 is plugged into a socket on the MMR). The sum of all of this is that you pretty much get what you pay for. 14 mhz 68000's. Haven't tried one so I can't comment. The 68010 is cheap and the gains are slight. The 68020 I tried resulted in a net slowdown and I had to give up either 6 meg of memory or my hard disk to use it. (Other '020 boards may work just fine). The 68030 in the MMR so far has worked the best, decent speed increases, works with all of my existing software (and hardware :), and should I sell my A-2000, I can put it in my A-1000 (it will also work in an A-500). If you can afford it, go for the Mega-Midgit-Racer. It will work in any 68000 based Amiga. Hope this has been: (A) Helpful, (B) Informative, (C) Interesting, or (D) None of the above. You will be tested at the end of this notes session!