Your peculiar find has inspired me to do some more digging-- also in accessmylibrary, but with a temp acct.
Apparently on or about Nov 1991, they clocked a 68030 at 55Mhz, added 128k of 15ns SRAM (replacing 32k of 20ns SRAM) and required 70ns SIMMs (and you thought regular IIfx ones were rare). It seems as if they've just re-clocked the whole processor and memory bus (everything else was on the 15.6672 MHz I/O Bus, the IIfx' Achilles' heel). In January Perspect took over marketing and raised the price and started requiring 60ns SIMMs. A 50 MHz version was also introduced, requiring only 70ns SIMMs. This makes some sense-- if you clock a processor 55/40 and speed the RAM likewise, it had better have about 8/11 the access times. "The developer said the stock IIfx processor is capable of 50-MHz performance in almost all cases and 55-MHz performance in the majority of cases, but Apple has conser-vatively chosen to clock them at 40 MHz. Being somewhat more adventuresome, TechNoir uses a faster clock chip to take advantage of the greater performance potential. "The second ingredient in Nexus fx performance gains is the larger and faster cache. TechNoir said the standard IIfx Fast Memory Controller inserts nine wait states for data retrieved from RAM but only two wait states for information retrieved from the cache." Compatibility would have been complete, unlike the TokaMac fx, or most 040 upgrades of the time. Indeed, even the TokaMac needed a replacement PAL chip at UK7 to be installed (A story for another day). Ain't MacWeek wonderful? And we have nothing like it now. Gregg Eshelman wrote: > --- On Sat, 7/11/09, Scott Holder <[email protected]> wrote: > > > As promised, I finally was able to grab my old Mac IIfx > > with the mystery > > accelerator from my parents'. > > > > It appears to be a Nexus FX by Tech Noir. > > I found that Perspect Systems Inc. bought Nexus Fx in early 1992. > > http://www.accessmylibrary.com/coms2/summary_0286-9249924_ITM > > Publication: MacWEEK > > Publication Date: 27-JAN-92 --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/vintage-macs?hl=en Low End Mac RSS feed at feed://lowendmac.com/feed.xml -~----------~----~----~----~------~----~------~--~---
