[ltp] (last thinkpad) convert to led backlight (R61)

Bret Comstock Waldow linux-thinkpad@linux-thinkpad.org
Thu, 11 Sep 2014 07:14:51 +1200

On 05/09/14 22:30, Paul Seelig wrote:
> If your R61 happens to be the 15"/4:3 variant, the following might be of
> high interest: http://www.theboardroom.info/led_mod.htm
> Unfortunately, the supply of native BOE Hydis LED UXGA appears to be
> next to nothing nowadays, so this might already have been an option of
> the long gone past.

I have this solution for my Frankenpads, and it works well.  I am
unaware of any functionality that is missing with this approach.

I chose this as I wanted a 4:3 IPS screen, high pixel density, matte
finish, and a display which wouldn't yellow and which would last for
many years.  The rest of the hardware for my machines are
T61-motherboard-in-T60-chassis Frankenpads which provides me with 8G RAM
and Penryn Core2Duo processors, SATA II.  The 14" 4:3 T61 motherboard is
the only one that will retro-fit into the 15" T60 chassis to allow this
- none of the T61 widescreen motherboards will physically fit into the
space.  The modem is lost as well.

Using an R61 wouldn't require sacrificing the modem, but appears to only
allow 4G RAM.

I did not do any before-and-after power measurements so I can't supply
any comparison information.  The screens are bright - with the CCFL
displays, I often ran at full brightness.  Now I rarely set backlight
above 50%.

One of them has NVidia NVS140m graphics, and thus runs OS X Mavericks.
OS X works at full native 1600x1200 resolution, and the scaling feature
works as well.

For Mavericks up to 10.9.1, sleep/wake works and there is a patch to fix
the SSL bug without upgrading.  Mavericks 10.9.4 works as well, but
loses the sleep/wake functionality.  You must have one of the NVidia
graphics chipsets to run OS X - Intel will not work (Apple offers no
drivers).  A wrinkle on this is that NVidia had a manufacturing quality
problem up until August 2008, and I read that boards before that time
die arbitrarily, and no, this is not something that can be fixed by
reflowing the motherboard in an oven.  I have a post 08/08 NVidia
motherboard, and so should not see this problem.  The Nvidia 570 chpset
also works with OS X.

My particular NVidia motherboard came from a stash a large corporation
ordered and used to service their own Thinkpad fleet.  It was
manufactured just for them post August 2008 and had never been installed
before I bought it and thus does not have ID numbers.  Lenovo and Apple
will disavow all knowledge of this machine...

It is possible that the Hackintosh community may be able to accommodate
Yosemite, but if not, I can revert to Linux, BSD Unix, or Windows.

The Intel graphics chpset is rock solid on T61 motherboards.  My second
Frankenpad has this and boots Xubuntu 14.04 LTS.

>From time to time, new caches of parts are discovered (a la my NVidia
motherboard and the LED-LCDs), so it might be worth your while to
establish surveillance on the ThInkpad forum
<http://www.thinkpads.com/forum/viewforum.php?f=11>.  Also, Frankenpads
(of various description) are sold there - you may find one more easily
than a supply of the LED-LCDs.  Tuus and ajkula66 on that forum
specialise in parts, conversions, and buying pallets of used Thinkpads
at auctions to find treasures...