CarolineM at 14:03, 13 September 2009

2009-09-13T14:03:08Z

← Older revision		Revision as of 10:03, 13 September 2009
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	> So what is ~~this~~, why do we need nomodeset on some computers and not others.		==So what is nomodeset, why do we need nomodeset on some computers and not others?==

	I don't know precisely what is causing the problem in this case, but		I don't know precisely what is causing the problem in this case, but

CarolineM: From an email by Bill Bogstad

2009-09-13T14:02:42Z

From an email by Bill Bogstad

New page

> So what is this, why do we need nomodeset on some computers and not others.

I don't know precisely what is causing the problem in this case, but
can give my general understanding of the class of problems.

It comes down to different computers having different graphics cards
(or the equivalent built onto the motherboard or into a laptop). They
all can draw pretty pictures. However, except for really basic (read
as slow) drawing, how the software needs to talk to the card is
different for every card. In the Windows
world, this means you need different graphics drivers for different
cards. The issue here is that
some new software/drivers for Linux which do something called "kernel
mode setting" for graphics cards haven't been sufficiently
tested/developed for the particular cards with which you are having
problems. Specifying 'nomodeset' when the system boots basically
tells the system to use an older set of software/drivers which does
work (but may be slower or have some other issues that people would
like to eliminate).

You might ask why not just make 'nomodeset' the default. Well the old
software has problems/is slower. Worse yet, it may not even work on
some newer cards. In this case the decision was made by the people
actually writing this part of the software we are using to make the
new method the default and allow an option to select the old one (and
request bug reports). If we were booting from a hard drive, it would
be easy to go in and make a trivial change on the machines with the
problem and never have to worry about it again. Unfortunately, CDs
are harder to modify.

If the machine has a floppy disk, the same small change can be made to
my floppy boot helper as well for machines that require/can use it.
If you are willing to have users select from a menu rather then boot
without any input, both the CD and floppy helper can give the user the
option of which mode to select. It should be possible to modify a USB
stick to have a menu as well.

Actually, I believe there actually is a menu hidden in all of the
current environments. If you hit a key (it may have to be escape)
fast enough, you can actually get a menu and you can manually add the
nomodeset option yourself every time you use that machine. It's
probably easier to show you how
to do this then to describe it.

Nomodeset - Revision history

CarolineM at 14:03, 13 September 2009

CarolineM: From an email by Bill Bogstad