From: nathan@laplace.biology.yale.edu (Nathan F. Janette)
Subject: NeXT-FAQ.internal: Questions about NeXT internal hardware
Reply-To: nathan@laplace.biology.yale.edu
Organization: Yale University, Department of Computer Science, New Haven, CT
Date: Fri, 13 Nov 1992 19:58:13 GMT
Expires: Fri, 18 Dec 1992 00:00:00 GMT

NeXT-FAQ.internal: Questions about NeXT internal hardware


*** Subject: I1. What can be done about older 030 NeXT cubes that have a fan  
that turns in the "wrong" direction?

The fan on older 030 NeXTs cubes sucks air out of the back of the cube  which  
means
that it draws unfiltered air in through the optical disk on the front of the
cube.  This causes optical disks to succumb to dust must sooner than cubes with
the new-style fan which turns in the opposite direction.

NeXT has apparently reversed their decision regarding fan reversal in the
case of machines that have been upgraded to 040 processor boards.  It is now
considered okay to reverse the direction of fans in these machines.  If you  
have
many third-party cards installed in your cube or an older processor board, you
may wish  to consider not reversing fan direction (overheating could become  a
problem).  In any case, do not reverse the fan's polarity, only reverse the fan
assembly itself.  Perhaps the best solution is  obtain the cleaning kit and OD
filter from NeXT.  

____________________________________________________________________________

*** Subject: I2. Can I connect SONY MPX-111N to my 030 cube?

The SONY MPX-111N internal 2.88 MB floppy drive which is shipped with all the
new 040 NeXT machines is *not* a SCSI device, therefor there is no way of
connecting that particular drive internally on an 030 system.  

____________________________________________________________________________

*** Subject: I3. Why does the OD continually spins up and spins down?

A big problem with the Canon optical drives is that air flows through the drive
to cool it.  Dust accumulates inside the drive causing it to fail with the
continuous spin-up spin-down syndrome.  NeXT as part of it's 040 upgrades
provides a dust filter to prevent this.  If your drive has this problem it
usually can be fixed simply by cleaning out dust from the drive.  NeXT sells a
cleaning kit for both the drives and the optical disks.  

____________________________________________________________________________

*** Subject: I4. How many colors can NeXT machines display?

The monochrome machines can display 4 gray levels.  You can use color apps on a
monochrome machine,  they will converted into monochrome images and dithered
accordingly.

Color NeXTstations can combine 4 bits of red, green and blue primaries for a
total of 4096 "pure" colors.  The imaging functions dither the image to produce
intermediate colors.

NeXTdimension can combine 8 bits of red, green and blue for 16,777,216.  There
are not 16 million points on the display so all can not be displayed at once. 
Further display technology limits the usable color space.

None of the NeXT products support color look up tables where the user can  
define
their own color palette on a per window basis. This feature is useful for
displaying images which have adaptive lookup tables, and display pure
grayscale images on the color NeXTstation.  On the NeXTdimension images can be
converted to full 24 bit representation.  

____________________________________________________________________________

*** Subject: I5. Why is my machine so slow when I run the monochrome and  
NeXTdimension displays?

There is a bug with the window system in which if you select the monochrome
display as your primary display the server will be much much slower.  The
solution for those wishing to use both displays is to select the color
(NeXTdimension) display as the primary display.  The most optimal
configuration at present with the NeXTdimension is to run only the color
display.  


____________________________________________________________________________

NeXT-FAQ Editor:
Nathan Janette nathan@laplace.csb.yale.edu


--
Nathan Janette		"I'm a NeXTstep man,
Dept MB&B, Yale Univ	 I'm a NeXTcube guy"
New Haven, CT
nathan@laplace.biology.yale.edu (NeXT)

Newsgroups: comp.sys.next.announce