magnus@THEP.LU.SE (Magnus Olsson) (10/15/90)
I'm getting a bit tired of my trusty 4.77 MHz XT clone, mainly because it's too slow. Now, the smart thing to do would of course be to buy a new computer, but I don't have very much money to spend, so I'm thinking of just upgrading the old machine with a new processor. Replacing the motherboard with an AT board seems rather attractive, but then I'd also have to get new RAM and new disk controllers which would add to the cost. And what would I do with the old board? I've heard about 80286 expanison boards that plug into an XT slot, for example something called the "Tiny Turbo", which are comparatively cheap. Of course, they won't turn my computer into an AT, but at least they'll speed it up a bit, and I assume I'll still be able to use my old peripherals. Does anybody out there have any experience with boards like this? Are they worth the price? How much faster do they make the XT? Is it still possible to switch back to the old 8088 processor (e.g. for copy-protected games that rely on 8088 timing)? Do they cooperate well with other XT expansion boards? I can't afford to pay more than about $300 (US prices, I'll be buying it over there) at the moment, so I'm afraid an Inboard 386 is out of the picture (pity!). Magnus Olsson | \e+ /_ Dept. of Theoretical Physics | \ Z / q University of Lund, Sweden | >----< Internet: magnus@thep.lu.se | / \===== g Bitnet: THEPMO@SELDC52 | /e- \q
simon@hpspwr.enet.dec.com (Curiosier and curiosier...) (10/15/90)
In article <9010150903.AA09539@thep.lu.se>, magnus@THEP.LU.SE (Magnus Olsson) writes... >I've heard about 80286 expanison boards that plug into an XT slot, for >example something called the "Tiny Turbo", which are comparatively cheap. >Of course, they won't turn my computer into an AT, but at least they'll >speed it up a bit, and I assume I'll still be able to use my old >peripherals. > >Does anybody out there have any experience with boards like this? Are they >worth the price? How much faster do they make the XT? Is it still possible >to switch back to the old 8088 processor (e.g. for copy-protected games >that rely on 8088 timing)? Do they cooperate well with other XT expansion >boards? I used to have a Tiny Turbo Xtra, a 12 MHz 286 to add to a 4.77/8 MHz XT. At the time it was a good choice -- for about $280 I was able to speed up the system considerably. For the home use it was enough. The thing had an 8K fast processor cache to circumevent the I/O bottleneck. Of course, it had its problems. One of them was the fact that the hard with an XT controller was not capable of working with the increased CPU speed. The disk was choking -- the transfer rate fell from 225KB/sec to 95 KB/sec. A few things had to be done: 1) Change the disk interleave factor from 3 to a new optimum 4; 2) Used controller BIOS ROM shadowing (RAMIT! program, available on request). This combination increased the rate to a tolerable 170 Kb/sec. All in all I should say that if all you can spend on the upgrade is $200 -300, an accelerator board may not be a bad thing. You can switch back and forth between a 286 and an 8088 modes with a flip of a switch at the back of the PC. I saw a regular Tiny Turbo (not Xtra) for 4.77 XT for around $200. Unfortunately the idea that one can increase speed of a PC quickly lead me to spending even more bucks to buy a 386SX within six months :-)! --------- Leo Simon simon@pwrvax.enet.dec.com Who is not liberal when young, does not have a heart. Who is not conservative when old, does not have a brain. -- W. Churchill
phil@brahms.amd.com (Phil Ngai) (10/16/90)
In article <16345@shlump.nac.dec.com> simon@hpspwr.enet.dec.com (Curiosier and curiosier...) writes: |All in all I should say that if all you can spend on the upgrade is $200 |-300, an accelerator board may not be a bad thing. You can switch back You can buy a complete 386sx motherboard for $300. That's a 16 MHz system with room for up to 8 megs of mostly no wait state RAM. Why mess around with anything else? -- The Bill of Rights isn't perfect, but it's better than what we have now.
simon@hpspwr.enet.dec.com (Curiosier and curiosier...) (10/16/90)
In article <1990Oct15.234045.15419@amd.com>, phil@brahms.amd.com (Phil Ngai) writes... >In article <16345@shlump.nac.dec.com> simon@hpspwr.enet.dec.com (Curiosier and curiosier...) writes: >|All in all I should say that if all you can spend on the upgrade is $200 >|-300, an accelerator board may not be a bad thing. You can switch back > >You can buy a complete 386sx motherboard for $300. That's a 16 MHz >system with room for up to 8 megs of mostly no wait state RAM. >Why mess around with anything else? This is of course true up to a point, and this was the route I went. However, an original XT box has only a 135 Watt power supply (may be not enough), you may need a different I/O card, and new floppy and hard disk controllers. You definetely need a new memory chip set, since an original XT uses 150 nsec chips. This all depends on the particular computer configuration. It may be a good idea to replace the whole motherboard, and it very well may be not. --------- Leo Simon simon@pwrvax.enet.dec.com Who is not liberal when young, does not have a heart. Who is not conservative when old, does not have a brain. -- W. Churchill
kaleb@thyme.jpl.nasa.gov (Kaleb Keithley ) (10/16/90)
In article <1990Oct15.234045.15419@amd.com> phil@brahms.amd.com (Phil Ngai) writes: >In article <16345@shlump.nac.dec.com> simon@hpspwr.enet.dec.com (Curiosier and curiosier...) writes: >|All in all I should say that if all you can spend on the upgrade is $200 >|-300, an accelerator board may not be a bad thing. You can switch back > >You can buy a complete 386sx motherboard for $300. That's a 16 MHz >system with room for up to 8 megs of mostly no wait state RAM. >Why mess around with anything else? That's not exactly a $300 solution, because then you have to add RAM, and probably will want to upgrade you HD controller. When I did this the performance on my 8-bit controller went into the toilet. $300 for the MB, $50 for a megabytes worth of 256K SIMMS, $100+ for a 16 bit HD/FD controller adds up to $450+. A $25 solution is to suck the 8088 out and plug a V20 in. That will double your speed according to Norton's SI, and may be sufficient for some peoples needs; if you're using the XT just for word processing, say. -- Kaleb Keithley Jet Propulsion Labs kaleb@thyme.jpl.nasa.gov causing trouble again.
mvolo@uncecs.edu (Michael R. Volow) (10/17/90)
I believe that replacement motherboards are better than accelerator cards from the standpoint of compatibility. A fairly cheap way to go is the hybrid 80286 motherboard (80286 processor, 8-bit 4.77 bus, PC keyboard compatibility), of which the Bullet (8, 10, 12 MHz models) (in Computer Shopper D.P. Computing or Marchand). They cost about $125-175 plus $50 for memory. They come in 5- and 8-slot models. We put on in an IBM PC at work (the 10 Hz version) and are very happy with it. We used the existing 8-bit hd controller and don't mind if the thruput is not up to AT standards. It's quite speedy on programs such as Word Perfect 5.1. On the other hand, if you have several already-graded components in your XT (e.g., large HD, high density floppy drive, VGA card) that could be moved to a '286, 386SX, or 386DX machine, it make sense to buy a bare bones AT-type machine (motherboard 16 bit HD/FD, Power Supply, fast memory), move the upgraded parts to the AT, and then sell the XT. I had the latter situation at home with my IBM PC. After completing the parts swap and sale of the PC, I found I had moved up to my 386SX for only $300 net! -- Michael Volow, Psychiatry, Durham VA Med Center, Durham NC 27712 919 286 0411 Ext 6933 mvolo@ecsvax.edu
labach@herald.usask.ca (Terry Labach) (10/17/90)
In article <1990Oct16.161726.1457@thyme.jpl.nasa.gov> kaleb@thyme.jpl.nasa.gov (Kaleb Keithley ) writes: >A $25 solution is to suck the 8088 out and plug a V20 in. That will >double your speed according to Norton's SI, and may be sufficient for >some peoples needs; if you're using the XT just for word processing, say. Unfortunately, Norton's SI, as has been pointed out many times, is the least useful of the Norton Utilities. My experience with the V20 is a 5-10% speed increase in computationally heavy tasks - not noticeable during your average word processing application. Mind you, it is a speed up, and for tinkerers like myself, it's enjoyable to get as much performance from the oldest hardware possible. If I want to do _real_ work, I use the UNIX box at work. :-) Terry ------------------------------------------------------------------------------ Terry Labach "And I concede your point too, that it's likely we heard more from the vested interests than Internet: we did from the little taxpayer...I suppose in labach@herald.usask.ca participatory democracy there will always be some whose voice is louder than others..." -Prime Minister Pierre Trudeau
magnus@thep.lu.se (Magnus Olsson) (10/17/90)
Thanks for the great response to my request - I've received loads of useful information by email! It seems that the best option for less than $300 or so is to change the motherboard, after all. Magnus Olsson | \e+ /_ Dept. of Theoretical Physics | \ Z / q University of Lund, Sweden | >----< Internet: magnus@thep.lu.se | / \===== g Bitnet: THEPMO@SELDC52 | /e- \q
phil@brahms.amd.com (Phil Ngai) (10/18/90)
In article <1990Oct16.161726.1457@thyme.jpl.nasa.gov> kaleb@thyme.jpl.nasa.gov (Kaleb Keithley ) writes: |That's not exactly a $300 solution, because then you have to add RAM, Yes, and you can sell your old mother. You can buy a megabyte for $50 these days. |and probably will want to upgrade you HD controller. When I did this |the performance on my 8-bit controller went into the toilet. $300 for Did your HD system SLOW down, or were you just dissatisfied that it didn't increase as much as you wanted. Did you try changing the interleave? The 386 should be able to support a faster interleave. |A $25 solution is to suck the 8088 out and plug a V20 in. That will |double your speed according to Norton's SI, and may be sufficient for |some peoples needs; if you're using the XT just for word processing, say. You get what you pay for. -- The Bill of Rights isn't perfect, but it's better than what we have now.
ndoduc@framentec.fr (Nhuan Doduc) (10/20/90)
In <1990Oct17.043104.29870@herald.usask.ca> labach@herald.usask.ca (Terry Labach) writes: >In article <1990Oct16.161726.1457@thyme.jpl.nasa.gov> kaleb@thyme.jpl.nasa.gov (Kaleb Keithley ) writes: >>A $25 solution is to suck the 8088 out and plug a V20 in. That will >Unfortunately, Norton's SI, as has been pointed out many times, is the >least useful of the Norton Utilities. My experience with the V20 is a >5-10% speed increase in computationally heavy tasks - not noticeable I've better luck and succeded in milking out 20% for very heavy CP task, and that for only 6.99 (+6%) us$ (why 25 ?). And if the task is CP and floating-point too, then an 8087 is a must (perhaps 100us$ ?). However, this is only valid for CP + FP tasks, not WordPerfect and so on ... --nh Nhuan DODUC, Framentec-Cognitech, Paris, France, ndoduc@framentec.fr or ndoduc@cognitech.fr, Association Francaise des Utilisateurs d'Unix, France, doduc@afuu.fr
kdq@demott.COM (Kevin D. Quitt) (10/20/90)
In article <1538@ftc.framentec.fr> ndoduc@framentec.fr (Nhuan Doduc) writes: >In <1990Oct17.043104.29870@herald.usask.ca> labach@herald.usask.ca (Terry Labach) writes: >>In article <1990Oct16.161726.1457@thyme.jpl.nasa.gov> kaleb@thyme.jpl.nasa.gov (Kaleb Keithley ) writes: >>>A $25 solution is to suck the 8088 out and plug a V20 in. That will >> My experience with the V20 is a >>5-10% speed increase in computationally heavy tasks - not noticeable >I've better luck and succeded in milking out 20% for very heavy CP task, and In my case, the code is table driven, so the CPU spends most of its time traversing said tables, rather than number crunching; the speed increase of the V20 is about 50%. In another case, an 8MHz V30 is actually 20% faster than a 10MHz 8086. -- _ Kevin D. Quitt demott!kdq kdq@demott.com DeMott Electronics Co. 14707 Keswick St. Van Nuys, CA 91405-1266 VOICE (818) 988-4975 FAX (818) 997-1190 MODEM (818) 997-4496 PEP last 96.37% of all statistics are made up.