R50p and T60/T60p LCD for T41p motherboard

[abbymat]

Will a R50p LCD and T60/T60p LCD work for a T41p motherboard ?

[ajkula66]

R50p shares the motherboard with T41p, so the answer is yes, it will work.

To get the T6x series LCD to work on this board you'd have to re-program the EEPROM...

Hope this helps.

[abbymat]

Thanks for the reply. Do you have any tutorials for reprogramming the EEPROM ? Is any special hardware requiered ?

[Johan]

... a strongly related issue was dissussed in the thread 15" Flexview UXGA screen for sale.

Please be a bit more specific about exactly what you have in mind; do you e.g. want to fit a T41p motherboard in a R50p lower base, and then mount this special-ThinkPad with a XGA or SXGA+ LCD from a T60? Or do you want to take a T41p motherboard in a R50p lower base, and then leave the original R50p UXGA LCD in place? In the latter case one question seems to be if the T41p motherboard (or rather, its GPU) will support UXGA - but that should be OK, since T41p's are using the ATI Mobility FireGL T2 GPU w/128 MB VRAM.

But: Please be a bit more specific about your intentions? Your project sounds interesting!

Johan

[Johan]

I found that the R50p is a Matte LCD while the T60/T60p is Flexview. Which would be better?

The R50p (UXGA, which is FlexView/IPS) LCD is matte, and T60/T60p LCD's are also matte. About T60/p LCD's, see the thread LCDs on T60/T60p - types, availability and other discussions.

Johan

[abbymat]

I have a T41p motherboard in a R51 case with 15" XGA LCD. Now I would like to upgrade to 15" UXGA.

Which would be better

1. R50p 15 "LCD

2. T60/T60p 15" LCD

Is there an image quality difference between the above two ?

Btw, flashing the EEPROM for the T60/T60p is quite difficult from what I read. Do you have any tutorials for reprogramming the EEPROM ? Is any special hardware requiered ?

[ajkula66]

Theoretically, Boe-Hydis LCD used in T60p (1600x1200) has a 500:1 contrast as opposed to all other FlexViews that have 400:1.

Is this difference worth the trouble of re-programming the EEPROM? Absolutely not in my opinion. And I've owned dozens of R50p units along with several T60p machines.

Stick with R50p's LCD. It will be easier to find, since it has also been used in T42p/T43p, and you won't be likely to notice much, if any, difference.

Good luck with whatever you decide.

[Troels]

I don't know anything about the T41/p, but the T42 does not rely on the EDID to get the correct image to show up on the screen, it uses different cables for this.
BUT,
as you are using a resolution with a motherboard that was never meant for this resolution, who knows if the UXGA cable will work. The difference between SXGA+ and UXGA cable lies just between two cut holes in the wires in the LCD cable. If this "method" is not detected on the T41 motherboards which is likely, you'd never get UXGA to work.
I still have found no method to either read or write to BOE-Hydis Lcds... both rely on two eeproms, which are wired up in some custom manner. It should be no problem with any of idtech's screens though... but i don't think you'll need an edid at all.

[abbymat]

My motherboard is a T41p motherboard with ATI FireGL 128mb which supports 1600 x 1200.

Suprisingly, I found a T60p UXGA LCD available for a lower price than the R50p LCD ! Thats why I'm looking into the possibilty of using it for my T41p motherboard.

From what I read, the T41p & T42p are exactly the same motherboard with different bios versions. So you say that there is no need to flash the EEPROM to get a T60p Boe-Hydis LCD to work on a T42p motherboard ? Thus the same should be applicable to the T41p motherboard ?

I dont want to risk flashing the EEPROM as it a complex process and requires some extra cables/adaptors & software.

However a R50p UXGA LCD, will work if I just plug it in right way ?

[ajkula66]

Who is the manufacturer of the T60p LCD that you've found?

[abbymat]

I found that the T60/T60p LCD is IDTech and NOT Boe Hydis. So will it work on the T42p motherboard without the necessity of reflashing EEPROM ?

[Troels]

The last batches of T60ps with UXGA featured Idtech (N150U3-L01) LCDs, which were produced near the end of the idtech factory closing. Actually, they are, like all never Idtech screens produced by Chi Mei, and not the IDtech factory in Japan, but they still have the IDtech brand name on it.

These last-stock Idtech LCDs were most likely new-old-stock that was in stock to take care of T42p/R50p/T43p/A31p repairs.
The only difference between these LCDs and the older from the T43p/T42p/R50p/A31p series is the EEPROM content, in order to make it compliant with T6x series, which rely on the EDID details to detect if the screen is "genuine".

It will work on a T42p with no mods or reflashings needed.
If you search ebay for IAQX10N, you could also get a QXGA LCD, but you'll need to order a QXGA R50p LCD cable too.

[abbymat]

So only the Manufacturer name is checked and not the LCD model number or something ?

And btw, what is checking what....is it the motherboard bios checking the LCD or vice-versa ? Is it possible to mod the motherboard bios which would be easier than reflashing the LCD EEPROM ?

I doubt the T41p GPU will be able to handle the QXGA LCD and anyway QXGA resolution it will be too hard to see on a 15" LCD !

[Troels]

There's a short, but scrambled, manufacturer specific string which must be available in the edid in order to make it work. I believe this is the only string it looks for. I've been able to see this specific string, but it does not have any meaning since it can't be represented with characters. It's a binary string.

Some specific part on the motherboard is checking the LCD edid to see if it contains the correct string, i believe it must be the bios, yes. A work-around might be possible, but i don't know how.

Anyways this is only the case with the T6x/R6x series. You can chose whatever LCD you want for the T4x/R5x series, maybe with exception for the T43/R52 series. As long, as the pinout is correct and you get the correct cable.
With the T6x/R6x at least, there is only one kind of cable for the 15", so the resolution is determined by the EDID, and screens are blacklisted if they don't have an edid or it does not have the correct "code".
If you install an LCD on a T6x/R6x series which has a wrong edid, it will just display vertical blue-red-grey stripes and won't boot into anything.

[abbymat]

Ok, I understood the LCD/Motherboard compatibility issue !

About the cables, is it difficult to replace them ? Should I change the cable in case I use a 15" T60 UXGA on a T41p motherboard ?

[Troels]

With patience and some hours of time, it's not difficult to replace the cable.
As you have a 15" XGA now, you'll neeed the R50p UXGA cable yes.
The T60 cables are different and have another point of entrance at the bottom of the screen lid, so it will not match up with a T4x or R5x motherboard.

[abbymat]

So do we need a specific model cable for the specific type of LCD ? That is, suppose instead of the R50p UXGA, I get a T43p UXGA do I have to get a T43p UXGA cable ?

Btw, do you have any links to tutorials on changing the LCD cable.

[Troels]

Hmm, i notice now that the cables for T43p/T42p UXGA are the same part no.: 91P6858
while that of the R50p is 91P6836

I don't know what the difference is, but i suspect the R50p cable may be very slightly longer, since the R5x shell is deeper than the T4x shell, a little bit longer cable is needed perhaps - just guessing.
Anyways, i wouldn't risk anything but to buy the 91P6836 cable.

BUT otherwise the LCD cable does not follow the screen, i.e. it wouldn't matter if you get a LCD meant for a T43p or R50p. It will work with both cables, but the R50p cable might have different proportions, but otherwise electrically the same.

I don't have any tutorials about replacing the cable. But follow the hardware maintenance manual for the R50p found at:
http://www-307.ibm.com/pc/support/site. ... 53169.html
And follow from page 105 and 119.