hundt@wind.bellcore.com (tom hundt) (08/29/87)
>>You can try Intel but your best bet is probably Cheetah International. They >>have either the 16Mhz or 20Mhz motherboards. Try them at 1-800-CHEETAH. > >...but make sure - as it, get it in writing - that they will accept >the 80387 chip. Even Intel's earlier motherboards won't. Is the 80387 packaged the same as the 80287 (40 pin DIP)? Or is it a square chip-carrier package? (If so, just look at the empty socket.) /-^-\ Thomas M. Hundt / BELLCORE Morristown NJ / hundt@bellcore.bellcore.com | | {seismo|ihnp4|ucbvax|decvax|ulysses|allegra|clyde}!bellcore!hundt /--_--\
lotto@wjh12.HARVARD.EDU (Jerry Lotto) (08/29/87)
In article <2245@bellcore.bellcore.com> hundt@wind.UUCP (tom hundt) writes: >>In reply to someone else (sorry I lost your name) >>>You can try Intel but your best bet is probably Cheetah International. They >>>have either the 16Mhz or 20Mhz motherboards. Try them at 1-800-CHEETAH. I did, thier motherboards are not quite ready yet. They implement a fast straight DRAM memory subsystem (no static column or cache) using 65 ns dynamic RAMS. They are awaiting 60 ns parts. Static cache may be available in the form of a processor daughter board for people in need. Motherboard is 8-layer and (they say) will accomodate 25 Mhz processors when they arrive. 80387 socket is standard (so is 80287 option). Phoenix BIOS, but they sounded interested when I told them about the AMI BIOS that I saw on a Mylex Mb. Mylex, BTW, is moving to Ca. They should be settled in about 1 week, but will be undergoing massive restructuring. >>...but make sure - as it, get it in writing - that they will accept >>the 80387 chip. Even Intel's earlier motherboards won't. > >Is the 80387 packaged the same as the 80287 (40 pin DIP)? Or is it >a square chip-carrier package? (If so, just look at the empty socket.) > > /-^-\ Thomas M. Hundt / BELLCORE Morristown NJ / hundt@bellcore.bellcore.com In case others have not picked up on it yet, the Intel Mb is designed to accept the 80387, but will not work with it. Anyone that used Intels specs for the 80387 emulator circuit to design theier Mb may be in the same boat. The sockets are different (Mylex supports an 80287 plug in directly), but an 80387 socket does NOT ensure a working floating point system. I agree w/ the original poster. Some systems mfrs reps do not even know that they make an 80287 Mb! Specifically get in writing that the thing WORKS (with (not just accepts) an 80387. Also find out how the socket is clocked. Can you speed up the 80387 socket w/o changing the speed of the 80386? Faster parts will be available, but NOT AT THE SAME TIME. Disclaimer: Disclaim. -- Gerald Lotto - Harvard Chemistry Dept. UUCP: {seismo,harpo,ihnp4,linus,allegra,ut-sally}!harvard!lotto ARPA: lotto@harvard.harvard.edu
jallen@netxcom.UUCP (John Allen) (08/31/87)
In article <2245@bellcore.bellcore.com> hundt@wind.UUCP (tom hundt) writes: >>>You can try Intel but your best bet is probably Cheetah International. They >>>have either the 16Mhz or 20Mhz motherboards. Try them at 1-800-CHEETAH. >> >>...but make sure - as it, get it in writing - that they will accept >>the 80387 chip. Even Intel's earlier motherboards won't. > >Is the 80387 packaged the same as the 80287 (40 pin DIP)? Or is it >a square chip-carrier package? (If so, just look at the empty socket.) The 387 data sheet from January, this year, describes the device as a 68-pin ceramic pin grid array (PGA) - "square". Thus it should be obvious whether a motherboard supports the 287 or the 387. John Allen ========================================================================= NetExpress Communications, Inc. seismo!{sundc|hadron}!netxcom!jallen 1953 Gallows Road, Suite 300 (703) 749-2238 Vienna, Va., 22180 =========================================================================
keithe@tekgvs.TEK.COM (Keith Ericson) (08/31/87)
>>> = somebody >> = me > = tom h then me, again In article <2245@bellcore.bellcore.com> hundt@wind.UUCP (tom hundt) writes: >>>You can try Intel but your best bet is probably Cheetah International. They >>>have either the 16Mhz or 20Mhz motherboards. Try them at 1-800-CHEETAH. >> >>...but make sure - as it, get it in writing - that they will accept ^^^^^^ >>the 80387 chip. Even Intel's earlier motherboards won't. > >Is the 80387 packaged the same as the 80287 (40 pin DIP)? Or is it >a square chip-carrier package? (If so, just look at the empty socket.) > My apologies - my use of "accept" is vague, prompting Tom's response. The problem is that earlier '386 motherboard do not generate the correct initialization sequence for the '387. The Intel moherboards prior to their "Fab 6" version are all guilty of this problem. (Don't ask me what the "correct initialization sequence" is because I Don't Know. Apparently neither did the Board designers :-)) So physically the '387 plugs in; logically (or electronically - I'm not sure which) it doesn't. keith (sorry for the confusion) ericson
gerard@tscs.UUCP (Stephen M. Gerard) (09/02/87)
In article <2245@bellcore.bellcore.com> hundt@wind.UUCP (tom hundt) writes: > >Is the 80387 packaged the same as the 80287 (40 pin DIP)? Or is it >a square chip-carrier package? (If so, just look at the empty socket.) The 80387 is packaged in a Pin Grid Array (square). WARNING!!!!! - Be very carefull to align the notched corner with the notch located on the socket. The orientation of the 80387 - MAY NOT - be the same as the 80386 the 80387. One of our people made that assumption, ouch!! I can assure you that the 80387 is absolutly useless after being powered up if it has been improperly inserted. 80387 key chain anyone???? It would have been nice if intel would have designed it to have an index pin. Or perhaps the sales of replacement 80387 will help finance the replacement of all the defective 80386's. :-) ------------------------------------------------------------------------------ Stephen Gerard - Total Support Computer Systems - Tampa - (813) 876-5990 UUCP: ...{codas, gatech}!usfvax2!tscs!gerard US-MAIL: Post Office Box 15395 - Tampa, Florida 33684-5395