Rotation and bigdesktop for HD4850(RV770?)

[Rodney M. Bates]

I have a new ATI Radeon HD 4850 video card.  I want to drive
two monitors, as bigdesktop, one rotated left, the other right.

(Note:  At the moment, I am driving this monitor setup with a
Matrox MGA G400, mga driver (which tells me in its log that it
disables acceleration when given a Rotate option), on a 700 MHz
AMD processor, with just barely usable performance for my purposes.
The new card is on a 2.5GHz Phenom.  So I presume that, even with
no acceleration, I would be at least somewhat happier.)

 From what I believe I have learned, the radeonhd and fglrx drivers
don't support rotation at all and the vesa driver at least does
not for this card.  This leaves the radeon driver as my apparent
only hope.

The radeon driver version packaged in Ubuntu 8.04 (driver version
4.3.0) does not recognize this video card, (whose chip is
apparently named RV770 and returns code 0x9442).

Question 1: Where can I find an upstream later version of this
driver, source and/or compiled?  I've looked at dozens of web
pages that talk about the radeon driver, but so far, no clue
where the code can actually be found.

Question 2: Can I expect a current or future version to do what
I want?

Question 3:  If not, can I get a current version to work by lying
about the chip with a ChipID line in my Device section of xorg.conf?
What chip id?

Question 4:  When I change the Driver line in the Device section,
just restarting X does not make the change effective.  I have to
reboot altogether.  Various documentation I have found says just
restarting X should be sufficient.  Am I doing something wrong?


-- 
-------------------------------------------------------------
Rodney M. Bates, retired assistant professor
Dept. of Computer Science, Wichita State University
Wichita, KS 67260-0083
316-978-3922
rodney.bates at wichita.edu