Message-ID: <3100001@rna.UUCP>
Date: Fri, 15-Mar-85 15:30:00 EST
Article-I.D.: rna.3100001
Posted: Fri Mar 15 15:30:00 1985
Date-Received: Tue, 12-Mar-85 07:43:52 EST
References: <2810@ncsu.UUCP>
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Nf-ID: #R:ncsu:-281000:rna:3100001:000:1219
Nf-From: rna!dan    Mar  9 15:30:00 1985
Xref: linus net.arch:746 net.decus:74 net.micro:8289

x
	You are basically right. The Pro 350 uses the F-11 chip set.
The KEF-11 chip is a floating point microcode extension. The time you
quote for floating point performance are for the 11/23 with the KEF-11
but should be close to correct. DEC also makes a bit-slice FPF-11
which is plug compatible with the KEF-11 chip and is said to be 5X faster
than the KEF-11 chip. You should be able to use that board if you provide
it with power (it normally obtains power from either the Qbus or Unibus
slot). There is no logarithm instruction (or any transcendentals) on any
PDP-11 machine.
	My benchmarks on an 11/23 and a PC/XT (amongst other machines) were
posted a while ago. For floating point performance, the 11/23 rated at .034
of an 11/780 (w/ FPA) while the PC/XT rated at .13, i.e. the PC/XT should
be as much as 3-4X faster than 11/23 (or the PRO350) in floating point.
Overall, however, the 11/23 rated at .16 of the 11/780 while the PC/XT rated
at .12 . The tested 11/23 had a fast disk.
	I further understand that the PRO350 disk is abysmally slow, so it would
not rate so high.
	Incidentally, the 11/73 floating point rates at .16, overall .35, so
the PRO380 should be more reasonable since it also uses the J-11 chip.