sdyer@bbnccv.UUCP (Steve Dyer) (06/19/85)
In the face of overwhelming silence on the net regarding my query about
replacement of the AT's 12mhz crystal with higher frequency crystals, I
forged ahead and installed a 18.4mhz crystal in its place. So far, I
have observed no deleterious effects. I would be willing to pass on any
experience I gain in this regard and am (still) eager to hear from any
other AT owners who have tried this.
--
/Steve Dyer
{decvax,linus,ima,ihnp4}!bbncca!sdyer
sdyer@bbnccv.ARPAroot@wlcrjs.UUCP (Randy Suess) (06/20/85)
In article <743@bbnccv.UUCP> sdyer@bbnccv.UUCP (Steve Dyer) writes: >In the face of overwhelming silence on the net regarding my query about >replacement of the AT's 12mhz crystal with higher frequency crystals, I >forged ahead and installed a 18.4mhz crystal in its place. So far, I >have observed no deleterious effects I did the same thing on my AT running Xenix, altho the only ~18 mhz crystal I had was 18.45. The AT would then hiccup every now and then. XENIX would go into various panic halts. I then stuck a 17.2573 (!!) crystal in and everything is hunky dorry. I guess when pushing the edge, it sometimes crumbles.. -- .. that's the biz, sweetheart .. Randy Suess Chi-Net - Public Access UN*X (312) 545 7535 (h) (312) 283 0559 (system) {ihnp4|ihldt}!wlcrjs!randy
dewa@ur-univax.UUCP (07/03/85)
I am curious if you had the regular math coprocessor 80287 installed too. I have heard that it normally operates at 4MHz (1/3 of the clock rate). How does it behave at beefed up clock rates? Thanks Rajiv
sdyer@bbnccv.UUCP (Steve Dyer) (07/03/85)
> I am curious if you had the regular math coprocessor 80287 installed too. > I have heard that it normally operates at 4MHz (1/3 of the clock rate). > How does it behave at beefed up clock rates? > Thanks Rajiv Yes, I have a 287 installed also. I guess it must be running at slightly over 6MHz, since my crystal is roughly 18.4Mhz. The IBM coprocessor diagnostics and a separate set of diagnostics from MicroWay all continue to work without errors--naturally, I can't vouch for how it will behave in the long term. So far I haven't noticed any anomalous calculations. By the way, I haven't noticed any heat-related problems--I can keep the machine on all day and it continues to work. -- /Steve Dyer {decvax,linus,ima,ihnp4}!bbncca!sdyer sdyer@bbnccv.ARPA