Thinkpad R60 (Frankenpad R601) - [SOLVED] SXGA+ problems (Possibly relevant to T60 / T61 too)

[natumbri]

Hi,

Short version: My SXGA+ screen doesn't work properly and although I have come up with a work around, I'd like to fix it properly, if possible.

Long version:

I have a TP that started life as a 4:3 R60 (9459-AQ9) with a 1024x768 display.
Everything worked fine.
Naturally, that meant it was time to pull it apart and start changing things.

First change: install a 1400x1050 SXGA+ screen, purchased for cheap from AliExpress (without first taking pictures or notes of the labels, manufacturer, etc, thereby missing the opportunity to be able to say anything useful about it ).
- machine boots fine, initial bios screen displays fine (at what looks like normal 1024x768), boots through to ubuntu, but desktop is 1280x1024.
- looks 'okay', but not what I wanted - not using the full resolution (resulting in a black border around the screen).
- reboot, go into bios and turn on screen zooming. This results in the 1280x1024 screen being zoomed to take up the 1400x1050 pixels of the LCD.
- also not what is required. turn off screen zooming.
- muck around with various things in /etc/default/grub. Eventually remove the 'nomodeset' option from the grub linux command line.
- reboot. bios screen comes up fine (per usual). boots through to ubuntu desktop.
- good news: 1400x1050; bad news: horizontal tearing and fuzziness all over the place, strange fuzzy line down the left hand side, per the attached 'before' images:


- give up (temporarily), and put up with 1280x1024 (by including 'nomodeset' in the grub linux command line)
- install 42W7822 motherboard, middleton bios, T7500 CPU, 6GB ram, SSD
- everything goes smoothly
- remove 'nomodeset' from grub linux command line, screen glitches return, as they were with the old r60 motherboard
- muck around further within ubuntu, including with xrandr
- notice, by some fluke, that the following command (which turns the display off and then on - a classic fix for nearly everything) occasionally fixes the display, per the attached 'after' images:

Code: Select all

xrandr --output LVDS1 --off && xrandr --output LVDS1 --auto

- great; perfect 1400x1050. bind that command to a keyboard shortcut and, after booting and logging in, press it until the display clears up (usually 2-3 times; occasionally it isn't required, occasionally 1 time is enough, occasionally it needs more than 3 goes but it always [so far] eventually works).

So, I can now use my Frankenpad R601 just fine, by resetting the display each time I start it (or resume from sleep, standby etc) as necessary. I just wonder if there is any way to fix this properly? Seems that it is definitely not a problem with the motherboard, since I've tried 2, and probably isn't a problem with the drivers, since I've tried various flavours of ubuntu (18.04, 20.04) and drivers from various repositories. Seems that it is most likely to be a problem with something on the LCD itself. But what?

Interested to hear if anyone has any thoughts!

Cheers,
Nik

[RealBlackStuff]

Use this to find out exactly which screen you have: https://www.binarytides.com/linux-hwinfo-command/
The T6x/R6x screens usually have an EDID-chip with screen info.
If that's missing (or wrong) on your screen, it can be fixed, but you may need to take the LCD out.

[natumbri]

Thanks for the suggestion!

Result:

natumbri@nik-r60:~ $ hwinfo --monitor        
26: None 00.0: 10002 LCD Monitor                                
  [Created at monitor.125]
  Unique ID: rdCR.MTMyZw7k9e4
  Parent ID: _Znp.3gR64TvADaC
  Hardware Class: monitor
  Model: "IDT LCD Monitor"
  Vendor: IDT "IDT"
  Device: eisa 0x000f 
  Resolution: 1400x1050@60Hz
  Size: 305x228 mm
  Year of Manufacture: 1990
  Week of Manufacture: 0
  Detailed Timings #0:
     Resolution: 1400x1050
     Horizontal: 1400 1448 1560 1528 (+48 +160 +128) +hsync
       Vertical: 1050 1051 1054 1062 (+1 +4 +12) +vsync
    Frequencies: 108.00 MHz, 70.68 kHz, 66.55 Hz
  Config Status: cfg=new, avail=yes, need=no, active=unknown
  Attached to: #22 (VGA compatible controller)

The year of manufacture is obviously wrong, but the rest seems right plausible. FWIW, the --gfxcard reports "Lenovo GM965 [X3100] on ThinkPad T61/R61" (as expected) and everything else looks normal/correct.

[RealBlackStuff]

Most likely that's an old IDT screen from the T4x/R5x series without EDID chip.

Here's some EDID-readout for SXGA+: viewtopic.php?p=596714#p596714
And a lot more info in that thread as well.

[natumbri]

Thanks a lot for the reference - I've had a good read through the whole thread.

Based on what is in that thread, I ran `get-edid | hexdump`:

natumbri@nik-r60:~ $ sudo get-edid | hexdump
This is read-edid version 3.0.2. Prepare for some fun.
Attempting to use i2c interface
No EDID on bus 0
No EDID on bus 1
No EDID on bus 2
No EDID on bus 4
No EDID on bus 5
No EDID on bus 6
1 potential busses found: 3
128-byte EDID successfully retrieved from i2c bus 3
Looks like i2c was successful. Have a good day.

... and obtained the following EDID dump:

0000000 ff00 ffff ffff 00ff 9424 000f 0000 0000
0000010 0000 0301 1e80 7817 cd0a 9175 4f55 268b
0000020 5021 0054 0000 0101 0101 0101 0101 0101
0000030 0101 0101 0101 2a30 8078 1a50 400c 7030
0000040 0013 e431 0010 1e00 0000 0f00 0800 1afa
0000050 01ff 063e ff7d ffff 00ff 0000 fe00 4900
0000060 5444 200a 2020 2020 2020 2020 0000 fe00
0000070 4e00 3531 5030 0a33 2020 2020 2020 e900
0000080

... which, according to the thinkwiki (and consistently with your suggestion), looks like it could be a:

15.0	1400x1050 FRU 92P6680 (ASM? P/N: 92P6671)	116,7	200	400:1	60ms	IDTech	N150P3-L01 R50, R51, T42, T43

But I'm not really sure where to next.

1. Does the screen have an EDID? The results from get-edid seem to suggest that it does, but the R5x/T4x don't require one.

2. Is the presence (or absence or, perhaps, corruption?) of an EDID likely to be causing the kind of problem I'm having (where the screen will work, if you turn it off and on enough times)? (Have people got screens with no EDID to work on thinkpads, like the R61, that require one?)

A bit of a mystery to me!

Thanks again for the pointers, I really appreciate the assistance.

Cheers
Nik

[RealBlackStuff]

These EDID readouts might help: viewtopic.php?p=574807#p574807 where he flashed the first EDID into the chip of the IDT-screen.
After this I'm out of suggestions.

[natumbri]

Thanks for your ongoing assistance with this - it is much appreciated.

The EDID in currently reported by my LCD is the second EDID in that post. Are you suggesting that I should flash my EDID with first one?

I've checked that first EDID with edid-decode and it reports an EDID for a Samsung SyncMaster 15.4" 1680x1050 WSXGA+ LCD:

edid-decode (hex):

00 ff ff ff ff ff ff 00 4c 2d 73 03 32 32 59 4d 
2c 12 01 03 80 2c 1e 78 2a 78 f1 a6 55 48 9b 26 
12 50 54 bf ef 80 b3 00 81 80 81 40 71 4f 01 01 
01 01 01 01 01 01 7c 2e 90 a0 60 1a 1e 40 30 20 
36 00 cb 28 11 00 00 1a 00 00 00 fd 00 38 4b 1e 
51 0e 00 0a 20 20 20 20 20 20 00 00 00 fc 00 53 
79 6e 63 4d 61 73 74 65 72 0a 20 20 00 00 00 ff 
00 48 39 58 51 41 31 38 39 38 34 0a 20 20 00 a3 

----------------

EDID version: 1.3
Manufacturer: SAM Model 883 Serial Number 1297691186
Made in week 44 of 2008
Digital display
Maximum image size: 44 cm x 30 cm
Gamma: 2.20
DPMS levels: Off
RGB color display
First detailed timing is preferred timing
Color Characteristics
  Red:   0.6494, 0.3349
  Green: 0.2832, 0.6054
  Blue:  0.1513, 0.0732
  White: 0.3125, 0.3291
Established Timings I & II
    720x400    70.082 Hz   9:5    31.467 kHz  28.320 MHz (IBM)
    640x480    59.940 Hz   4:3    31.469 kHz  25.175 MHz (DMT)
    640x480    66.667 Hz   4:3    35.000 kHz  30.240 MHz (Apple)
    640x480    72.809 Hz   4:3    37.861 kHz  31.500 MHz (DMT)
    640x480    75.000 Hz   4:3    37.500 kHz  31.500 MHz (DMT)
    800x600    56.250 Hz   4:3    35.156 kHz  36.000 MHz (DMT)
    800x600    60.317 Hz   4:3    37.879 kHz  40.000 MHz (DMT)
    800x600    72.188 Hz   4:3    48.077 kHz  50.000 MHz (DMT)
    800x600    75.000 Hz   4:3    46.875 kHz  49.500 MHz (DMT)
    832x624    74.551 Hz   4:3    49.726 kHz  57.284 MHz (Apple)
   1024x768    60.004 Hz   4:3    48.363 kHz  65.000 MHz (DMT)
   1024x768    70.069 Hz   4:3    56.476 kHz  75.000 MHz (DMT)
   1024x768    75.029 Hz   4:3    60.023 kHz  78.750 MHz (DMT)
   1280x1024   75.025 Hz   5:4    79.976 kHz 135.000 MHz (DMT)
   1152x870    75.062 Hz 192:145  68.681 kHz 100.000 MHz (Apple)
Standard Timings
   1680x1050   59.954 Hz  16:10   65.290 kHz 146.250 MHz (DMT)
   1280x1024   60.020 Hz   5:4    63.981 kHz 108.000 MHz (DMT)
   1280x960    60.000 Hz   4:3    60.000 kHz 108.000 MHz (DMT)
   1152x864    75.000 Hz   4:3    67.500 kHz 108.000 MHz (DMT)
Detailed mode: Clock 119.000 MHz, 459 mm x 296 mm
               1680 1728 1760 1840 ( 48  32  80)
               1050 1053 1059 1080 (  3   6  21)
               +hsync -vsync
               VertFreq: 59.883 Hz, HorFreq: 64.674 kHz
Display Range Limits
  Monitor ranges (GTF): 56-75 Hz V, 30-81 kHz H, max dotclock 140 MHz
Display Product Name: SyncMaster
Display Product Serial Number: H9XQA18984
Checksum: 0xa3

I'm not so sure that it would be a good idea to flash that EDID to my 4:3 1400x1050 panel? I could try, but it just doesn't seem like much good can come of it...

Thanks again for your ideas - this really is a mystery to me, so having someone else make suggestions is a great help.

Cheers,
Nik

[RealBlackStuff]

That [linked] post is not entirely clear and might also have typos in it (15.4" instead of 15.0").
Check the 2nd EDID, that might be what you need.
If your EDID-flashing works, you won't damage the screen by entering wrong info.
Just make sure to at least save the old EDID before you start.
A new EDID might display wrong, but flash the saved one back in and you'll be fine again until you find the proper EDID.

[natumbri]

That [linked] post is not entirely clear and might also have typos in it (15.4" instead of 15.0").

Agree.

Check the 2nd EDID, that might be what you need.

Based on my check (using edid-rw), the 2nd EDID is the EDID I currently have - byte-for-byte identical. It is EDID for a 15.0" 4:3 IDT N150P3.

If your EDID-flashing works, you won't damage the screen by entering wrong info.
Just make sure to at least save the old EDID before you start.
A new EDID might display wrong, but flash the saved one back in and you'll be fine again until you find the proper EDID.

Good to know - thanks for the pointers.

Do you have any thoughts about why - if I have an EDID problem - sometimes the lcd displays fine, and sometimes it doesn't?

Cheers,
Nik

[RealBlackStuff]

Don't forget that screen is at least 10 years old!
There might be some corrosion on the contacts, which could be anywhere.
I'd start with removing the cable-connector from the back of the LCD, rub those gold contacts with an eraser until they shine, remove any debris before reinserting.
You could also try and reseat the LCD-cable on the motherboard a few times.
If still no luck, the LCD might need to be replaced.

[natumbri]

Thanks again - yes, I think some sort of bad connection or something along those lines is a pretty good candidate, given how intermittent the problem is. I'll try your suggestions and report back here. If the problem is a consequence of the ageing of the components, maybe the information about it, and about the things I tried to fix it, will become increasingly relevant to others.

Cheers,
Nik

[natumbri]

Update - I tried the EDID for a Samsung SyncMaster 15.4" 1680x1050 WSXGA+ LCD (ie. the first EDID in the [linked] post). Here's how I did it and what happened.

Loading the new EDID
Instead of burning the EDID to the lcd, I told linux (ubuntu 20.04) to ignore the lcd EDID and load an EDID from a file instead. To do so, I:
1. used the EDID data from the first block in the the linked post and the linux command 'xxd -r' to create a binary EDID file ('modified_edid.bin')
2. created a /lib/firmware/edid directory and put a copy of 'modified_edid.bin' in it
3. followed the instructions in this post on launchpad.net

What happened?
1. The computer booted, and the kernel used the edid file, which is good.
2. Having booted 3 times, including a cold boot, the weird horizontal line issue described above does not appear, which is GREAT (although, n=3 isn't a huge number of tests, remembering that even with the original EDID it works, sometimes)
3. Linux thinks the LCD is 1680x1050 even though it is really 1400x1050. As a result, the display kind of wraps around, and, for example, when you scroll the mouse off the edge of the screen, to the right, it appears on the left hand edge of a column 280px wide towards the LHS of the panel (images below). Which is... well, not unexpected frankly. But not great.


What I did next
1. I made a binary edid file from the second block in the the linked post and told linux to use that. As with the first, linux loaded the EDID fine. The resolution was the correct 1400x1050, but sadly (though perhaps not unexpectedly), the original problem - the fuzzy horizontal line issue - returned.
2. I made a binary edid file from the hex in this post. Linux loaded the EDID fine, the resolution is correct, and, happily (so far), no sign of the original problem. (My panel is neither yellow nor dim, FWIW.) I've now made this my default EDID and will test for a few days, to see if the problem is fixed, or if it returns. If it is fixed, I might try to burn the new EDID to the panel.

Fingers crossed, and thanks again to RBS for his encouragement!

Cheers,
Nik

[RealBlackStuff]

Good to hear you got it going!

The "yellow and dim" as mentioned only applies to [some] screens, not all suffer the same fate.

[natumbri]

I just went and checked my T60 - the EDID in that screen says that it is a LG Philips LP150E05-A2 and it is yellow and dim (right). Horrible compared to the now apparently fully functional panel in my R601 (left), which says that it is an IDTech N150P3-L01, but which apparently only works with a LP150E05-A2 EDID.



Go figure.

Cheers,
Nik