Trying to upgrade Toshiba NB550D screen from WSVGA to WXGA

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carnbot

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I'm still waiting for my LCD cable to arrive. Did you double check that the screen was attached properly?
Is it an LG screen like the original?
This is a setback as we can't confirm if anyone has managed to upgrade this model yet.
 

Wrathlon69

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I double, triple and quadruple checked. I'm confident I know exactly what the problem is:

In the older NB500 series it has a low level hardware control to initialise the screen properly at 1366x768 whereas our model doesnt. All is not lost however, as this means its purely a signal output problem.

Evidence pointing to this:

1) I found a thread of a guy who was replacing the LP101WSA screen (Our factory panel) with a LP101WH1 (The panel we are trying to use) in a different laptop. One person solved it by extracting the graphics module from the BIOS of a different laptop and imported it into the BIOS for his laptop and got it going as it now contained the profile needed to run that panel correctly.

2) In another thread, a guy doing the same thing managed to resolve the problem by compiling a new intel graphics driver with custom signal settings to override the defaults. This made the panel work perfectly in Windows but didnt resolve the issues outside of windows obviously as its a driver fix. This doesnt matter as the signal, although bad, is more than adequate for BIOS and setup, etc.

The first finding points to it being a BIOS limitation, the second points to that limitation being able to be compensated for in the graphics driver.

I actually have some experience in this - my desktop runs a Radeon 5970 and I use an old FW900 24" Widescreen CRT. The problem is ATi drivers cant custom res simply like nVidia ones can and the monitor supports well beyond its official resolutions. I made a custom monitor INF that overrides the EDID detection and tells the graphic card specifically what signal to output and it works. I have a monitor that officially supports 2304x1440@60hz outputting 2560x1600@72hz.

I tried the same trick on the netbook with the new panel and it seems the 6250/6290 accepts this override just fine as I went from bad signal to no signal at all but still had backlight control indicating the panel was just out of range. When I plugged the default panel it, it tried to draw 1366x768 but cut it off because the panel isnt that big and it had a green artifact at the bottom meaning that it did, in fact, modify the graphics card output.

I have documentation of both panels with their signalling info and they are VERY different panels, hence why it doesnt work properly. Given what I've found, what others have solved with and from my limited testing so far, I should be able to make a custom driver to enable the panel to work correctly just need a bit of time to play around and experiment.

Dont lose hope just yet because I'm about 90% confident I can fix this.
 

Wrathlon69

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Well bad news unfortunately. Ive tested every single combination of everything in both Windows and in Linux with custom outputs etc and its always the same.

There must just be some slight difference between the LVDS controller on these boards and the one on the older NB500 that lets the older one use the panels.
 


Hi :)

Sorry but I did tell you...we change hundreds of screens a month....

All the best Brett :)
 

carnbot

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That's a shame, something to do with the fact that NB500 is intel Atom and NB550D is AMD C-50 maybe?
It's annoying that this graphics card, good though it is for a netbook can't scale easily. Maybe someone else will find a workaround sometime....
I'm still tempted to fit a WXGA screen as it was usable on mine for browsing reading and writing, only annoying if watching a film really and I don't do that on my netbook. When someone releases a thin usb powered hdmi touchscreen then we have another option.
 

Wrathlon69

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There is always the possibility of a bad batch or a bad panel here. I guess try a new cable and see. Ive been reading up on lvds non stop and I really cant see a reason for this not working.
 

Wrathlon69

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I think its something specific with the panel we are using - whats the model number on yours?

The reason being is I found a 15.6" laptop here thats LED 1366x768 and 40 pin LVDS cable and plugged it in to my NB550D and it works perfectly so its NOT a problem with 1366x768 specifically so much as its a problem with this laptop and that specific board.
 

carnbot

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The screen I bought was sold as LG PHILIPS LP101WH1(TL)(A​3) TLA3

But I can't check the exact number on the screen as I don't have it any more. Also I can't be sure it didn't work because I damaged the connector or because of incompatibility, I'm guessing incompatibilty based on your experiments.
I've noticed there are TLA1 and TLA2 versions of this screen, do you know what these numbers mean? My original screen is TLN1 so perhaps it needs a TLA1...?
 

Wrathlon69

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Not sure what they mean but I think the WH1 range is incompatible...mine was a LP101WH1(TL)(A2). The A3 is just the next revision from the A2.

I have a Toshiba C650D here with a 40 pin 1366x768 15.6" Samsung LTN156AT05-S01 screen in it and it works perfectly on my netbook. The LP101WH1(TL)(A2) works perfectly on the C650D as well so I think it's just that specific panel and our specific laptop.

There is a 10.1" 1366x768 Samsung LTN101AT03 Panel that matches ours (6 bit LVDS, 40 pin, TN TFT Panel) - I'm going to order one of these and see if it works.

Our laptop can obviously drive a 1366x768 panel just fine, Im typing this right now on a 15.6" 1366x768 LCD panel sitting on my bench next to my Netbook with a cable hanging out the side - I just think that specific panel is a no.
 

Wrathlon69

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OK Seeing as Im Australia (No idea where you are) and the panel is coming from Canada it will be a few days before it gets here. Fingers crossed this one works.
 

carnbot

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Great, that sounds promising, fingers double crossed for this panel to work!
Seeing as this little netbook can handle full HD via hdmi out I'm confused as to even why Toshiba didn't put 1366 as the native screen as they barely cost much more than the wsvga screens.
I'm in the U.K by the way.
 

Wrathlon69

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Well this panel is $9 more than the original OEM panel :p

Really shits me, its an amazing netbook otherwise. The only problems really are the 1024x600 screen, 1GB RAM and Windows 7 Starter.

Windows 7 is neither here nor there, the RAM is a total non issue as its so cheap, just this panel.

At least Ive proved it CAN drive a 1366x768 panel just fine, which is a good start...just have to find the right panel :D
 

carnbot

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Yes I think Toshiba really mis-sold this netbook as it's more capable than how they sell it. I've installed an SSD and 4GB of ram running windows 8 pro and it runs really well for something this size. I've even read that the 8GB sticks work too.
 

carnbot

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Here's hoping....:) I've managed to get my old display back up and running again with a new lcd cable for now.
 

Wrathlon69

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Im taking this time to hack up a 4 port USB hub and rewire the data pins from my USB module so that the power is still supplied by the board but the data is provided by the hub to give me an extra spot to connect the touch screen panel I bought :D
 

Wrathlon69

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OK panel arrived and...

...the idiots sent me the LP101WH1 panel again. Despite specifically ordering the LTN101AT03 panel. So sent in a ticket to try and get this resolved. Fuck me.
 

carnbot

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Only just saw this, that's frustrating. I hope the new one works.

I've had problems with the auto brightness of my screen since refitting the old one. Plugged in it works fine but on battery the screen flickers. Not sure if it's something I've done or if there's a fault somewhere. Anyhow I've managed to disable the auto brightness so on battery its stuck on 50 as a workaround.