bose@iuvax.UUCP (09/12/86)
Can anyone give me the details of the NEC V20 chip stuff. I have an XT and would like to speed things up a little. Does the NEC chip have any incompatibility drawbacks?
sbanner1@uvicctr.UUCP (S. John Banner) (09/18/86)
In article <1500065@iuvax> bose@iuvax.UUCP writes: > >Can anyone give me the details of the NEC V20 chip stuff. I have an XT >and would like to speed things up a little. Does the NEC chip have >any incompatibility drawbacks? To use it, just pull out the 8088, and plug in the V20, and away you go. I had the job done about 4 months ago, and have had no problems with it. I have however heard of some incompatablility problems with it, but these all occur when the software has internal timing loops, instead of the Dos timer call (tut, tut, non-portable code). The only specific instance of this that I know of is LoadRunner (which doesn't bother me, because it didn't run on my machine without the V20), though I hear it also affects some other games, one or two HardDisk controlers, and a few (very few) other things. S. John Banner UUCP: ...!uw-beaver!uvicctr!sbanner1 BITNET: ccsjb@uvvm EAN: sbanner1@uvunix.uvic.cdn
gordon@inmet.UUCP (09/25/86)
When I installed a V20 in my PC, I found that DISKCOPY and FORMAT didn't work any more. Since it was an 8Mhz chip, I had increased the clock speed at the same time and perhaps that was the cause of the problem. In the end, the performance improvement was so negligible (5 or 10% with the standard clock speed) that I decided to put the 8088 back and buy a "PC Elevator" which is a card with an 80286 on it. The V20 with an 8Mhz clock is definitely the most bang (50% speedup) for the buck (about $25 including crystal). It just bugs me when basic utilities don't work. -- Mike Gordon (ihnp4!inmet!gordon)
cramer@kontron.UUCP (Clayton Cramer) (09/28/86)
> > When I installed a V20 in my PC, I found that DISKCOPY and FORMAT > didn't work any more. Since it was an 8Mhz chip, I had increased > the clock speed at the same time and perhaps that was the cause of > the problem. In the end, the performance improvement was so > negligible (5 or 10% with the standard clock speed) that I decided > to put the 8088 back and buy a "PC Elevator" which is a card with > an 80286 on it. The V20 with an 8Mhz clock is definitely the most > bang (50% speedup) for the buck (about $25 including crystal). It > just bugs me when basic utilities don't work. > > -- Mike Gordon (ihnp4!inmet!gordon) DISKCOPY and FORMAT both require that the processor run at 4.77 MHz. (Timing dependencies involving the disk controller.) The FAST88 kit I have gives you a switch to go back to 4.77 MHz for this exact reason. Clayton E. Cramer
guest@csustan.UUCP (Chris Rhodes) (09/29/86)
In article <1091@kontron.UUCP> cramer@kontron.UUCP (Clayton Cramer) writes: > >DISKCOPY and FORMAT both require that the processor run at 4.77 MHz. >(Timing dependencies involving the disk controller.) The FAST88 kit >I have gives you a switch to go back to 4.77 MHz for this exact reason. > >Clayton E. Cramer Gee, my pclone, which supposedly runs at 8mhz (norton says 1.6 relative speed, haven't done the math yet) runs diskcopy and format perfectly fine....in fact, all my utilities (and all my software for that matter) work fine. Good thing, too, because I'd have to move a jumper on my motherboard if I wanted to take it down to 4.77. Has anybody had a problem with diskcopy and format not working at 8mhz? /* Chris Rhodes / Shooting Shark * Currently cowering behind lll-crg!csustan!guest * real uucp : lll-crg!csuh!shark -or- lll-crg!ptsfa!harlie!shark * My opinions *are* those of csustan! Yeah, they made me spokesman, ah, */ president of the university! Yeah, *that's* the ticket!
jeffd@ittvax.ATC.ITT.UUCP (Jeff Denenberg) (09/29/86)
> > When I installed a V20 in my PC, I found that DISKCOPY and FORMAT > didn't work any more. Since it was an 8Mhz chip, I had increased > the clock speed at the same time and perhaps that was the cause of > the problem. In the end, the performance improvement was so > negligible (5 or 10% with the standard clock speed) that I decided > to put the 8088 back and buy a "PC Elevator" which is a card with > an 80286 on it. The V20 with an 8Mhz clock is definitely the most > bang (50% speedup) for the buck (about $25 including crystal). It > just bugs me when basic utilities don't work. > > -- Mike Gordon (ihnp4!inmet!gordon) Please don't blame the V20. Your problem was the speedup to 8Mhz. There are other chips in your pc that are sensitive to the clock rate and those need to be replaced as well. You must also be careful of add-on boards. Some of those will have problems at 8Mhz (Try running at 6Mhz, you might have better luck. Jeff Denenberg ..!decvax!ittvax!jeffd
owen@gt-eedsp.UUCP (Owen Adair) (09/29/86)
In article <1091@kontron.UUCP> cramer@kontron.UUCP (Clayton Cramer) writes: >> When I installed a V20 in my PC, I found that DISKCOPY and FORMAT >> didn't work any more. Since it was an 8Mhz chip, I had increased > >DISKCOPY and FORMAT both require that the processor run at 4.77 MHz. I am running an 8Mhz PC with the V20 and never had a problem running these utilities or any other program. -- Owen Adair, Digital Signal Processing Lab, Ga. Institute of Technology uucp ... !{akgua,allegra,hplabs,ihnp4,seismo,ulysses}!gatech!gt-eedsp!owen Disclaimer: My employer is not responsible for, nor does it care, what I say here or anywhere else.
gritz@homxb.UUCP (R.SHARPLES) (09/30/86)
I would imagine that the drive controller dependencies mentioned are hardware based and an 8mhz clone that can operate at 4.77 or 8 would have a driver hardware that operates at 8 for sure, and probably 4.77. However, IBM saw no need to equip their hardware for anything but 4.77mhz. RPS homxb!gritz
jallen@netxcom.UUCP (John Allen) (09/30/86)
In article <208@csustan.UUCP> guest@csustan.UUCP (Chris Rhodes) writes: >In article <1091@kontron.UUCP> cramer@kontron.UUCP (Clayton Cramer) writes: >> >>DISKCOPY and FORMAT both require that the processor run at 4.77 MHz. >>(Timing dependencies involving the disk controller.) The FAST88 kit >>I have gives you a switch to go back to 4.77 MHz for this exact reason. >> >>Clayton E. Cramer > >Gee, my pclone, which supposedly runs at 8mhz (norton says 1.6 relative >speed, haven't done the math yet) runs diskcopy and format perfectly >fine....in fact, all my utilities (and all my software for that matter) >work fine. Good thing, too, because I'd have to move a jumper on my >motherboard if I wanted to take it down to 4.77. Has anybody had >a problem with diskcopy and format not working at 8mhz? > >/* Chris Rhodes / Shooting Shark I've got a FAST88 too, which "Norton's in" at a big 1.7 at 7.14 MHz. How's this? Your clone probably has two clocks, one for the processor, one for the rest of the system, hence FORMAT & DISKCOPY run fine. (It's also possible your clone isn't sensitive to clock speed the way a PC is.) The FAST-88 on the other hand runs the whole system at the higher clock speed. John Allen ========================================================================= NetExpress Communications, Inc. seismo!{sundc|hadron}!netxcom!jallen 1953 Gallows Road, Suite 300 (703) 749-2238 Vienna, Va., 22180 =========================================================================
cramer@kontron.UUCP (Clayton Cramer) (09/30/86)
> In article <1091@kontron.UUCP> cramer@kontron.UUCP (Clayton Cramer) writes: > > > >DISKCOPY and FORMAT both require that the processor run at 4.77 MHz. > >(Timing dependencies involving the disk controller.) The FAST88 kit > >I have gives you a switch to go back to 4.77 MHz for this exact reason. > > > >Clayton E. Cramer > > Gee, my pclone, which supposedly runs at 8mhz (norton says 1.6 relative > speed, haven't done the math yet) runs diskcopy and format perfectly > fine....in fact, all my utilities (and all my software for that matter) > work fine. Good thing, too, because I'd have to move a jumper on my > motherboard if I wanted to take it down to 4.77. Has anybody had > a problem with diskcopy and format not working at 8mhz? > > /* Chris Rhodes / Shooting Shark > * Currently cowering behind lll-crg!csustan!guest > * real uucp : lll-crg!csuh!shark -or- lll-crg!ptsfa!harlie!shark > * My opinions *are* those of csustan! Yeah, they made me spokesman, ah, > */ president of the university! Yeah, *that's* the ticket! Well, to be more precise, the BIOS of the IBM PC/XT has a problem running DISKCOPY and FORMAT at speeds other than 4.77 MHz. I've been most recently fighting with a clone called Terminator LT that uses a 286 but an XT-like BIOS (in fact, the serial I/O BIOS code is a copyright infringement on IBM -- I'm glad I didn't buy it) and runs at 10 MHz -- and can't FORMAT floppies! (The company JUST discovered it and is issuing BIOS ROM upgrades!) Clayton E. Cramer
jamesa@dadla.UUCP (James Akiyama) (10/01/86)
The problem may be in the BIOS. I believe that many PC's use software timing loops to determine system timeouts (e.g. waiting for the disk drive to return seek complete). These prevent the PC from becoming hung if a disk drive is bad but are clock speed sensitive.
john@hp-pcd.UUCP (john) (10/02/86)
<<<<< < Please don't blame the V20. Your problem was the speedup to 8Mhz. There are < other chips in your pc that are sensitive to the clock rate and those need < to be replaced as well. You must also be careful of add-on boards. Some of < those will have problems at 8Mhz (Try running at 6Mhz, you might have better < luck. < Jeff Denenberg < ..!decvax!ittvax!jeffd < /* ---------- */ The other chip that can cause problems with the FORMAT command is the DMA controller but replacing it with a faster one doesn't help. The problem is that if you increase its clock to anything greater than 6 MHZ then the DACK pulse produced during a verify operation is to short for the floppy controller to recognize. Read or write operations have wait states inserted so they will still work ok but a verify operation will return DMA overrun errors. Clones designed for 8 MHZ opertion will normally run the DMA chip at 1/2 the CPU frequency to allow these utilities to work. John Eaton !hplabs!hp-pcd!john
rob@gould9.UUCP (rob) (10/02/86)
In article <6200047@inmet>, gordon@inmet.UUCP writes: > > When I installed a V20 in my PC, I found that DISKCOPY and FORMAT > didn't work any more. Since it was an 8Mhz chip, I had increased > the clock speed at the same time and perhaps that was the cause of > the problem. In the end, the performance improvement was so > negligible (5 or 10% with the standard clock speed) that I decided > to put the 8088 back and buy a "PC Elevator" which is a card with > an 80286 on it. The V20 with an 8Mhz clock is definitely the most > bang (50% speedup) for the buck (about $25 including crystal). It > just bugs me when basic utilities don't work. > > -- Mike Gordon (ihnp4!inmet!gordon) Did you check to see if your memory chips were rated at the new clock speed? They were probably 200 ns chips. I upgraded my ram to 120ns and the V20 worked fine...
lau@ubc-ean.UUCP (10/02/86)
> >DISKCOPY and FORMAT both require that the processor run at 4.77 MHz. >(Timing dependencies involving the disk controller.) The FAST88 kit >I have gives you a switch to go back to 4.77 MHz for this exact reason. > >Clayton E. Cramer How come the DISKCOPY and FORMAT that comes with the ZENITH Z158 and Z148 work on those machines? Both of them have a switchable clock speed (4.77 and 8 Mhz). I always have the machine running at 8 and have used both programs without any problems.
gt5909b@gtfelix.gatech.EDU (DERVAN) (10/07/86)
I believe that there are a few enhancements. Somewhere out there there is a file that explains the new features of the V20/30. I will try to find it. -Richard