Subject: Re: New chip in TWGS (sources for oscillators) Path: lobby!newstf02.news.aol.com!audrey04.news.aol.com!not-for-mail From: supertimer@aol.com (Supertimer) Newsgroups: comp.sys.apple2 Lines: 55 NNTP-Posting-Host: ladder05.news.aol.com X-Admin: news@aol.com Date: 25 Oct 1999 05:36:34 GMT References: Organization: AOL http://www.aol.com Message-ID: <19991025013634.01524.00000793@ng-fp1.aol.com> cornelio@san.rr.com (L. Cornelio) wrote: >supertimer@aol.com (Supertimer) wrote: > >>If not, I suggest getting the 50Mhz and 40Mhz units. >>12.5Mhz TWGS (50Mhz oscillator) almost always >>works, but with a 40Mhz unit, you can fall back on >>10Mhz operation if necessary. > >FYI, my ZipGSX works fine w/ a 40 mhz & no chip swap. >Does that maybe imply that w/ a chip sway 50 or even 60 will work? Very likely yes. Especially the 50. What was the Zip clocked at before? If you have the 8Mhz processor of the Sanyo design, you have a very overclockable chip. It does not hurt to give it a try. >I was wondering which cards were considered more >"easily upgradeable" the TWGS or the Zip..... It depends. TWGS is simpler to upgrade all other things considered. It has cache RAM fast enough so that to upgrade it usually involves changing only the oscillator and the CPU. For minor speed upgrades, sometimes only the oscillator needs to be replaced. But the TWGS is older. It came with either 6Mhz or 7Mhz CPUs of the older design. The 6Mhz version was not very overclockable. Thus, for major speed upgrades you need a new CPU for the TWGS. The Zip GS started with CPU chips of the type used in the TWGS, but the Zip GS survived long enough that they started using the Sanyo versions of the chips. These came in either 8Mhz or 14Mhz versions. These were VERY overclockable. Some people have pushed the 8Mhz chip to 15Mhz, for example. So if you have the "good" 8Mhz chip, you can often avoid a new CPU and thus save a step compared to the TWGS. BUT if your Zip GS started out with the older 7Mhz CPU of the non-Sanyo design, it is usually harder to upgrade than a TWGS. That's because 7Mhz Zips came with slow cache RAM chips. So on older 7Mhz units, the cache RAM chips often needed to be replaced. This is difficult because fast cache chips are now available only in the 300 mil packages. Zip GS uses 600 mil ones. Thus adapter sockets must be used. These are rather expensive ($7 each). It is either that or solder a new row of socket pins for each cache RAM chip to plug into.