Upgrading my screen, help?

Hi.
I have a Toshiba SATELLITE P750-10R.
It comes with a samsung ltn156at05-u09 panel with 40 pin connector. It is a 15.6', 1366×768 panel and I would like to upgrade but I perhaps to a nice 95 gamut screen with higher resolution.

I have an NVIDIA GeForce GT 540M graphic card as well as intel 3000. From the Nvidia webpage: "Dual-link DVI Support. Able to drive industry’s largest and highest resolution flat-panel displays up to 2560x1600 and with support for High-bandwidth Digital Content Protection (HDCP)."

I have been looking at the AUO B156HW01 V4 but dont know if it will fit or work. The AUO is an old screen and perhaps there are better ones out there now in the same price range. I would like a matte screen.

Does anyone have a clue?

 

Funny how they designate 768p as "HD" ...

Anyway, a physical fit is not an issue. But you need to be aware of 1-channel versus 2-channel LVDS. Similar situation here: Vostro 3560 screen upgrade (read that, please).

So, having read that ... you need a 2-channel LVDS cable for this to work. Unfortunately the P750 series doesn't seem to sport a 900p or 1080p model (doesn't matter which; both use a 2-channel type). Note that the Satellite P755D-S5172 is listed as 900p, but this cannot be verified anywhere else, so that seems an errata on NBC's part. Now, getting a matching cable is not an issue; it's likely you can buy a FHD cable from another Toshiba series. What is problematic is whether or not the additional wires are even connected on the motherboard itself. Another matching thread; Vostro 3550 screen upgrade?.

So ... willing to test this?

 

Thanks for the reply!!!
I did disassemble the computer to find out if the pins were attached. When I got so far I saw that it was a completely different connector on the other end of the cable.

The connector is 30 pin with all legs soldered to the multilayered pcb. There was no way to determine which legs was actually connected to a route or just there for support of the connector.

The name JLVDS was printed next to the connector.
And I also checked the mother board and it is a
PHQAA LA-6831P
REV 2
2010-12-24
With approximal schematics here.

I cant really interpret the information I have collected could you help?

 

Ah, brilliant work; the schematic's helpful :thumbsup: (page 25);



Now, the TXOUT1, -2 and -3 with their +/- is your 6-bit data channel, including CLK +/- (clock) that's 8 pins. For a 2-channel cable you need a further 8 pins and these are not on this JLVDS connector. According to your schematics these are termed T ZOUT and connect to a separate connector; JLVDS 1. Without this one there's no FHD possible, with this connector you could even run a 3D panel.

Unfortunately, motherboard schematics may refer to different revisions, and think it's likely yours looks like this one:



So there's a label where the JLVDS1 might've been, but with this revision board it's unpopulated.

 

Thanks for the brilliant support!! You are a true GURU
Yes it is unpopulated.
I wonder if you think it is possible that the connector is just unpopulated and the routs are in fact connected in the other end, so just the connector is missing for a working superconnection ?
The ting is I know how to solder and it would not be a problem, if a connector not is superhard to get hold of, for me to solder one in place. It looks like it is surface mounted. Do you think that would do the trick for me to get a better screen? And moddig could be fun as well.
If not do you have any suggestion of a 1366×768 replacement screens that are good bang for buck?

Thanx!
/Johannes

 

It's possible, though a bit of a gamble. Well, if you're open to soldering there's no need for a connector. Acquire a matching cable and splice the second 10-pin terminator into its individual wires and solder these to the 'blobs' on the pcb.

The cable ought to look something like this or this one. Be aware that there's lots of cables with a secondary split-off, but these are most commonly intended for webcam and/or speakers. You can easily tell because their pin count is only 4 or 6. Also, as the JLVDS and JLVDS1 are in such close proximity it's to be expected the correct cable would have its split-off close to motherboard end as well. Like in the first example, only that one's probably too short, being intended for a 13.3".

One thing you might test before proceeding; take multimeter and measure the JLVDS1's soldering points on the mb when the laptop's running. With any luck pin #9 will be powered; it's the 5V one and the second pin counting from either side of the row.

For a 768p screen do an advanced search on panelook and make a compare, ditching all non-matching panels. Take the remaining list and look up each model on notebookcheck; chances are some of those panels will have been reviewed in all kinds of laptops (example review of the B156HW01 V4).

 

I have not had time to dismantle the laptop and messure. But I was thinking of doing so. I cant make any sense of the scematics but I need to messure against gnd and wonder if any pin is gnd.

I'm not sure if I want to take the gamble of buying a cable and a screen and possibly not being able to return them. If I get 5V do you think it is lightly to work?

I'm thinking of settling with a 768p. I want something good or descent since the current is bad in saturation I don't want to just get the same screen.

But I cant get heads or tail out of the advanced search. could you help me?
As I stated before my screen is a samsung ltn156at05-u09

Many thanks for your help :thumbsup:.
/Johannes

 

Fair chance, yes. It doesn't make sense if they'd wire voltage, but not the others.

The details on that panel are a bit scarce, but I'll wager it's a matte (since colour saturation is poor).

To find a compatible screen, narrow down to these specifications:

• Composition·······Panel ("Cell" is without backlight)
• Min/max size······15.6"
• Pixel resolution··1366×768
• Aspect Ratio······16:9 (to make sure width:height matches)
• Surface···········Glossy (deeper colours than the same panel with matte finish)
• Interface type····LVDS
• Lamp Type·········WLED

That leaves these 110 panels to choose from; 768p is very common in basic (read: cheap) laptop models. Actually, you need to narrow down further to these details (which you can't select in Panelook's search box):

• Interface Class·····LVDS (1 ch, 6-bit)
• Interface pins······40
• Connector location··bottom left

Note that that "1 ch, 6-bit" is a severe limitation when it comes to choosing a "better screen", there's only so much information that this most basic of cable types can accommodate. Expect an improvement, but not a day/night difference, excepting the matte vs. glossy change. To make sure a panel is 6-bit; Color is 262k maximum, anything higher requires a better cable. For the 40 pins add panels to "Panel compare" and it lists up to 15 panels side-by-side, you can then drop all panels that do not match those specifications. Connector location is not listed, but most will be bottom left anyway, it's just a final check before purchasing a new lcd.

When you've made that final list; post them here, I'll make a lookup search list for NBC (like this N156BGE-L21), there's bound to be a few that have been reviewed.

 

I dismantled the notebook and measured the voltage on the 2:nd pin from either side and it was a square wave on one of them and no voltage on the other.

the wave had a period of approx 20ms (=50Hz) and peak -5V to +4V (peak to peak approx. 8-9V) with this looks:



(I'm not 100% sure about the voltage since I don't know how well the oscilloscope is calibrated.)
I don't know how to remove from the list but I have compared all of the panels.
There were some difference in Interface brand and model but almost all were 40 pin. All were with 262k.

Only one was with 30 pin,
there were some that had no info so I post them here as N/A.

N156B6-L02 ----30pin
LTN156AT11-A01 --- N/A
LTN156AT02-A02--- N/A
LTN156AT02-A01--- N/A
BT156GW03 V.0--- N/A

This is a lot of panels that match... 105 to be exact...
What do you think?

 

Your posts are some of the most informative posts on this entire forum. Honestly learned more in 2 days reading your posts than anywhere else about various upgrades/swaps of notebooks... thank you sir.

 

Since there is no question about an upgrade any more but to find a decent 1366x768 resolution screen I posted the question in a new thred. which can be read here.

Many thanks for all the help.

/Johannes