The Notebook Review forums were hosted by TechTarget, who shut down them down on January 31, 2022. This static read-only archive was pulled by NBR forum users between January 20 and January 31, 2022, in an effort to make sure that the valuable technical information that had been posted on the forums is preserved. For current discussions, many NBR forum users moved over to NotebookTalk.net after the shutdown.
Problems? See this thread at archive.org.

    T61 mobo & LCD woes

    Discussion in 'Lenovo' started by bgalakazam, Jul 2, 2011.

  1. bgalakazam

    bgalakazam Notebook Enthusiast

    Reputations:
    0
    Messages:
    47
    Likes Received:
    0
    Trophy Points:
    15
    I have trouble with getting the LCD working on my T61. Currently I cannot get a working LCD in OS mode. Some of the LCDs work in POST and BIOS, others not. I am starting to believe something is wrong with the motherboard or my wiring because I NEVER get the 3 leds (power, battery, hdd) on the T61, no matter which inverter or screen I use. Only the wifi led works. Same inverters on my T60 work with all leds. Here is a bare setup of the T61, CPU, RAM, the long black cable (with or without, doesn't matter), LCD, speaker, keyboard.

    Info:
    - motherboard 42W7649 (14.1" non-wide, NVS 140M)
    - only wifi led works on T61, regardless of inverter
    - There is no problem in using external monitor, so GPU is working.
    - Speaker beeps work, but you hear a crackling sound when logging in Windows and when shutting down (short somewhere?)
    - I have tried testing all possibilities with stock BIOS and Middleton's BIOS. Results are the same, so BIOS is OK.
    - I have tried all 3 EDIDs in the complete qxga thread, same results (again, QXGA works like a charm on T60)

    Combinations (all tests were done with both 15" LCD cable from T60 and a 14" LCD cable from T61 == same results):

    T60 + 15" SXGA+/UXGA inverter (42T0079) + QXGA LCD = POST and BIOS and Windows/Linux LiveCD all work
    T60 + 15" XGA inverter (42T0077) + 15" XGA LCD = POST and BIOS and Windows/Linux LiveCD all work

    T61 + 15" XGA inverter (42T0077) + 15" XGA LCD = POST and BIOS work, Windows/Linux LiveCD no backlight
    T61 + 14" SXGA+ inverter (41W1479) + 14" SXGA+ LCD = POST and BIOS and Windows/Linux LiveCD no backlight
    T61 + 15" SXGA+/UXGA inverter (42T0079) + QXGA LCD = POST and BIOS and Windows/Linux LiveCD no backlight
    T61 + 15" XGA inverter (42T0077) + QXGA LCD = POST and BIOS work, Windows/Linux LiveCD doesn't work

    It is strange that T61 + XGA inverter powers on the QXGA up to OS, but the SXGA+/UXGA doesn't do that.

    Can you shed some light? I tried looking if there is a short somewhere, but couldn't find. The LCDs are working fine on my T60. The T61 is flawless when booting on external monitor. The BIOS is stock or Middleton's, no change. I have reset CMOS several times, no change.

    Any help would be appreciated as I would like to get my computer up to speed again. Cheers.
     
    bgalakazam, Jul 2, 2011
    #1
  2. bgalakazam

    bgalakazam Notebook Enthusiast

    Reputations:
    0
    Messages:
    47
    Likes Received:
    0
    Trophy Points:
    15
    It's the 140M nVIDIA issue, I found out. You may lock the thread.
     
    bgalakazam, Jul 6, 2011
    #2
  3. ZaZ

    ZaZ Super Model Super Moderator

    Reputations:
    4,982
    Messages:
    34,001
    Likes Received:
    1,415
    Trophy Points:
    581
    I might suggest if you want to keep the machine, buying a T61 board with the Intel GPU.
     
    ZaZ, Jul 7, 2011
    #3