Thinkpad T61p with Nvidia graphics

[Roberto Ragusa]

Matthew Saltzman wrote:

> With the original F8 spin, my T61 nVidia did not Just Work after
> install.  It works with the vesa driver (except that the backlight never
> goes off),

My experience with a T61p with nvidia gfx card.

The vesa driver works well, and the 2D performance is acceptable;
there is no Xv support so a there is a high CPU usage when playing
video, and there is no CPU-free full screen rescaling, but you
don't have performance problem. I'm not totally sure, but I think
it was possible to play an (unscaled) HDTV video; both mplayer
and X will use a lot of CPU, but this machines is a dual core. :-)
Vesa driver means no 3D acceleration (bad for Google earth).
It also means poor power management: I didn't manage to go
below 24-25W with vesa, but with the nvidia driver it goes down
to about 15W.
Hibernation works perfectly. Damn missing power management...

> and it works with the nv driver after fully updating (modulo
> a couple of issues like suspend).

I remember to have tried this options too and discarded it
quite soon; my hope was to have better power management than with
vesa, but it wasn't so and I got a crash when switching to
a textual console, if I remember correctly.

> It works well with the latest nvidia
> drivers from Livna (including suspend to RAM, but not hibernate).

I'm currently using the nvidia binary driver.
It is fast in everything (2D, 3D, video).
It has good power management.

But, in addition to "only-free philosophy" issues (8 megabytes
of binary blob in my kernel!) it is a costant pain if you
want to reliably use suspend/hibernate.

After a lot of experimentation and tweaking:
- suspend to RAM apparently works quite well, but I'm not using
it too much
- fedora standard hibernation didn't work
- tuxonice based hibernation (cubbi kernel) works after heavy
tweaking, but not perfectly; I can often hibernate and resume with
an open nvidia binary X session, but the resume process always
stalls for about one minute during resume (some CPU livelocking
message appears in the log with a stack trace deep inside the
nvidia stuff) and the suspend process sometimes (15-20%) hangs
the machine for no apparent reason (and your session is then lost).

If the hibernation problems don't improve I will use suspend
to RAM more often.

>> Everything else works pretty much out of the box. And is fast as hell.
>> Could just be a little lighter and have a bit more of autonomy (3h is
>> not enough) but i'm still tweaking the power mgmt bits (got mine
>> yesterday).

With powertop I get to around 15-16W with nvidia binary.
The 9 cell battery is 84Wh.
The 6 cell should be 2/3 of that.

> Three hours is all I've been able to get with the 6-cell battery.  If
> you discover anything magic, I'd like to know.  Thanks.

Powertop is your friend.

You can also disable the radios with the hardware switch, but I got
some nasty interrupt craziness and crashes when reswitching them
on. (!)

Other BIOS related details:
- SATA should NOT be in compatibility mode
- you have to activate the CPU virtualization if you want to play
with kvm

Best regards.
-- 
    Roberto Ragusa    mail at robertoragusa.it