Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!apple!uokmax!drtiller From: drtiller@uokmax.ecn.uoknor.edu (Donald Richard Tillery Jr) Newsgroups: comp.sys.amiga.hardware Subject: Info Message-ID: <1991Apr5.194147.25387@uokmax.ecn.uoknor.edu> Date: 5 Apr 91 19:41:47 GMT Organization: Engineering Computer Network, University of Oklahoma, Norman, OK Lines: 121 In a message From: erk@americ.UUCP (Erick Parsons) > I have come to these conclusions (be they right or wrong) > > o In order to fully utilize the potential of a 68030 accelarator > In this case the Mega Midget Racer by CSA, one needs at least > 256K of 32 Bit Static ram on board to realize any significant > bang for the buck, with 512K being optimum as that's max for > onboard ram without the addition of a daughter board. You will see an extreme speed increase with 32 bit Dynamic RAM added as well. > o 32 bit microprocessors are kludgy on 16 bit busses like that > of the A500. True, but the 68030 has a dynamic bus size so it is not really a "kludge" to use it in a 16 bit system. However, this is true for the 68040 which has an exclusively 32 bit bus and requires external circuitry to address the standard 16 bit bus. > ? What is in fact the minimum amount of 32 bit wide ram necessary > to make the 68030 a blazingly fast, efficient accelarator ? > Is static ram preferable to Dynamic Ram ? According to my info, Static RAM _used_ to be inherently faster than Dynamic RAM. Since Dynamic RAM uses less current and can be squeezed into a smaller package, it has been preferable to Static RAM. As a result, research has allowed Dynamic RAM to be manufactured as fast as Static RAM (or very close) for a cheaper price, too. Anyway, what this means to you is that NO, Dynamic RAM is not necessarily preferable to Static RAM. Fill the Static RAM area of that card and then add as much Dynamic RAM as you can afford when you have the money for it. For "blinding" efficiency, you should have at least 512K of 32 bit memory (WorkBench 2.0 has a 512K ROM and you should plan ahead). This won't speed up all of every program (depending on it's system usage) but it will make a VERY noticable improvement in system operation. To notice further improvements you need to run the actual programs from 32 bit RAM. > ? Is my 16 bit ram going to slow things down? I have a sizable > investment in ram to date (5 megs) Well it depends on how you look at it. The 16 bit memory won't speed up things, so in a way that is true. However, if the memory is of the same format as the 32 bit card requires, you can use it as 32 bit memory (there is no difference between 32 and 16 bit memory, just their buses) and you won't lose the money you've invested in RAM. If not, check comp.sys.amiga. marketplace :-) > ? Do these accelarators use the same simm memory expansion modules > that other expansion boards use ? i.e. 1M x 8, and is the fact that > it is 80ns access time a detriment to burst mode caching ? Sorry, I can't help you with the particulars of the Mega Midget Racer. I understand, however, that most accelerator boards take into account the burst mode and work with it as they can. I doubt that 80nS RAM will be a detriment to the system (80nS is rather fast after all). > ? Will I realize any significant increases in speed in general with > Caching disabled on a 33 MHZ '030' / 68882 / 512K 32Bit Static Ram ? I really don't notice a great deal of difference in speed during real- world program execution with or without my cache installed. It makes a great deal of difference when a loop of 256 bytes or less is being executed, but it looks like in real life, this is rarely the case (this can become a factor with the 4K cache in the '040). > ? " Caching enabled ? > > > o A math co-processor will speedup dramatically CAD, 3D-rendering > programs and Spreadsheets that are floating point intensive. Yup. > ? Will the addition of a 68882 co-pro. do anything for such things > as flight simulators and or simulations. (Standard answer to almost any computer/electronics question:) Depends. If the program recognizes and uses the co-processor if it's there, of course it will help. Otherwise, it might not. I found a library replacement for the mathtrans.library that will use the 68881/2 for calls to this library. If the simulator uses this library as it should, this will speed up the simulator as well. (I think it is called fasttrans.library) > o There seem to be two versions (if not more) of '030's floating > around these days. There is the MMU and non MMU. ????????? I haven't heard of a 68030 without the MMU. That would probably be a totally different number (68020? :-) > ? Would it be worth it at some later date to have gotten the MMU > '030' ? i.e. Unix implementations running rampant in the forseeable > future. I don't know whether there are really many progs out yet that use the MMU other than a couple of debuggers and the developer software boot program. I feel certain that there will be MMU requiring programs in the future so it could come in handy. > Opinions Wanted Provided :-) > o There are a thousand things that I would like to get for my Amiga > but only so much money. Would I be better off buying an AdSpeed > accelarator for a little over 200.00 and increasing data storage ? > > -or- > > o Should I go with a 33 MHZ MMU w/ 68882 co-processor and 512K of > Static Ram as a package for well over a thousand dollars and > forget about buying anything else for expansion till next April ? I'd suggest if you have a hard drive, you get the latter, if not the former. Rick Tillery (drtiller@uokmax.ecn.uoknor.edu)