T41p SXGA+ LCD upgrade T43 1875-DLU

[kodi]

Hello,

I am having problems upgrading my T43 1875DLU with the Intel 900 chipset to use the T41p SXGA+ LCD. The backlight comes on, but no graphics. Output through VGA port is fine.

Any help on this is appreciated, Thanks

[ulrich.von.lich]

Have you changed the LCD cable to the one for SXGA+?

[kodi]

I used the native cable that came with the t41p. I didn't replace the LCD, rather I just did a full assembly lid/screen swap. The connectors/hinges seemed identical - I assumed they were compatible. I didn't read anything about problems; I guess am I missing something?

[ajkula66]

And I would imagine that you'd need to replace the inverter as well.

[ulrich.von.lich]

Yes, the SXGA+ panel uses a different inverter too. Thanks ajkula!

Since you swapped the entire LCD assembly, then you probably already have both. The last thing I would suggest to do is a BIOS update.

Here's a thread which might be helpful.

Good luck!

[kodi]

Ok so the FRUs for the T41p sxga are:

Inverter: 26p8464
Cable: 91p6787
LCD(sammy): 11p8384

T43 xga:
Inverter: 27k9972
Cable: 91p6941

This link suggests that the cable is only for xga??
http://www-307.ibm.com/pc/support/site. ... 58431.html

So any thoughts on this before I swap them both? I fear swapping the inverter; couldn't that have ill effects on my precious lcd?

Thanks for all the feedback, ulrich, wrong link? I read a few threads here with a similar issue, but they didn't seem have a definitive conclusion. If theres one out there I'd be very grateful.

Thanks again
[/url]

[richk]

I have never used a 14" SXGA+ screen on a T43 with Intel graphics. None were made with that configuration. The only SXGA+ screens that came with Intel graphics were with "CTO" models, and I have no idea what they used.

On all the other machines (T40/T41/T42, and T43 with ATi (28xx), the inverter on 14" XGA and SXGA+ machines are the same. The part number changed between T42 and T43, but they just changed the number. The inverters are interchangable. If you swap a whole assembly, it will work fine. This means that either your new screen is bad or any SXGA+ screen just doesn't work with your motherboard. If nobody else has more info, I am taking apart a couple of T43s this weekend. I think one has Intel graphics, so I can try an SXGA+ panel and see if it works.

[kodi]

Yes, I am thinking they are incompatible too.

I have confirmed that the LCD panel is good, and I performed the swap with first the inverter and then the cable. The monitor has the same behavior in each case. Back-light comes on, but no graphics.

From the looks of things it doesn't look like the 900 can push 1024?:
http://www.thinkwiki.org/wiki/Intel_Gra ... erator_900

[ulrich.von.lich]

Sorry about the link. Here's the correct one:

http://forum.thinkpads.com/viewtopic.ph ... c&start=30

I read the posts again carefully, but I don't think they were talking about the same issue as you are experiencing.

The inverter should be ok. There are only two kinds of inverters, one for XGA and the other for SXGA+/UXGA. The Intel 900 is capable of driving an internal SXGA+ LCD, given the existence of some preconfigured R52s that have both 900 and SXGA+. So there's nothing wrong with the concept of your upgrade.

Now I'm suspecting the issue is caused by the LCD cable. The one in my SXGA+ T43 is 91P6942. It's a cheap part, so you should try it out once you get a chance.

I would also suggest you to wait and see what some forum gurus would say.

Hope it helps!