[SUCCESS] P377SM-A 4K Display Upgrade

Does LCD fits properly inside or you had to do some mechanical modifications. Which version of BIOS/EC are you using? Make a great video and share your joy of upgrading. Make the difference! Be the First!

 

Some Mechanical mod needed. To fit it, there is 2 solution i tried: by modding the lcd support, cutting a space both of down support and extend those above. Or The easier way, is taking the frame of lcd from a compatible screen, just putting it arround the new display and glue it or silicon it arround with the frame (where the screen should be fix with screws). we also have to remove the metal frame fixed in barebone because the driver of new screen is down ( not behind the display).
Also, no contact between metal barebone and display. we can use anything such as tape.

My bios is from Prema.
i would love to make a video but i have not such more time for modding this year, i dont even find the time to mod ( dremel) the barebone+heatsink for the msi 1070 gpu.

 

I originally tried doing this/something similar (see earlier in the thread). Ultimately it seemed that for some reason, when the 3.3v rail was loaded, the screen would draw too much current and pull the voltage down to about 1.9V which was out of spec for the screen to even turn on.

Its strange because the 3.3v and 5v are generated by the same circuit.. . . Do you have any insight?

 

The 1M Ohm resistor R388 used in the absence of PLVDD_sel to pull the signal high to select 3.3V may have too high of a resistance for the power FETs used in the P377SM (design error by Clevo). I'd lower its value. You can just pencil it a little to test this. Make sure PLVDD_sel is not connected.

If this doesn't get you 3.3V then I'd bypass both PLVDD select and 3.3VS circuits and wire straight to the 3.3V power source, called VDD3 in the service manual schematic. Jumper PJ11 would be a good place to solder a wire to. Page 68 has this circuit in the service manual.

 

Small update:

I tapped directly into VDD3 as @Khenglish suggested and everything works. No voltage drop and no more need for the buck converter.

 

That should make things a fair amount more compact and efficient

 

Guys, good news here, I have an old p370em and I just upgraded my screen to 4K thanks to this thread!

 

Nice, what panel and what steps did you take exactly?

 

Good! What panel did you use?

 

I was using the same AUO panel and cable as OP. Did exactly as he described but no tricky work to obtain 3.3v for the panel, I have 3.3v by default an my panel works at 3.20v.

The only problem I have is flicker (lastly not so much, don't know why) and fixing the panel since the holes on panel are totally mismatched respect to original one.

Oh, I see you guys are representatives of 2 companies. Sorry to say but this panel model and this clevo pc are not completely compatible physically.

 

It's not something we would offer on an older model anyway, but it's always good to get confirmation if other users feel like giving it a go.

 

To fix the flicker, try putting more decoupling capacitance on the 3.3V rail.

 

Hello guys!
Followed this thread to upgrade my laptop with some degree of success:

http://forum.notebookreview.com/threads/p377sma-4k-display-upgrade-waiting-for-parts-to-test.786555/

The thread is closed now that's the reason of this one.
I'm calling for guys who had success in the old thread to help me: DARCODER, aarpcard, khenglish, akaraah, t456

I have bad flickering and then black screen, please take a look and suggest:

https://drive.google.com/open?id=1oKYs5WwfAdznrioZ04QMx0hU2Zvq_x7S

the voltage on LCD is 3.23v. I read all 12 pages and tried all suggestions from other users. Decoupling capacitor didn't work on 3.3v rail. I used a 3300uF capacitor.

Taping the LCD so it didn't touch the hinge didn't work since there is a connection of LCD metal part with GND through the LCD cable. Without the cable the is no connection between the LCD and hinges, I have a multimeter for that.

I was disparate an bough another LCD from eBay, it also flickers.

Guys, please help to bring to the life this laptop! Thanks in advance!

 

That looks like you are getting interference on the eDP cable from the motherboard. Do you have any exposed sections of the cable that are not covered in EMI tape?

A test for this is to drop the refresh rate using the custom resolution tool in the Nvidia control panel. If 60 Hz mostly works, you'll probably be fine at 40 to 50 Hz.

 

Just tried. I'm on mac, used a mac specific utility. Have only 3 options: 48/50/60HZ. When switching HZ the screen goes black...
Do you remember if with 5v there issues? Maybe I can try it.

 

5V will work but you will have some display issues. Screens are usually rated for up to 4V before strange things happen.

 

I looked at the video. Did you by chance alter the length of some of the EDP channel wires? I had the exact same artifacting when I accidentally cut an EDP channel twisted pair while making my cable and soldered it back together. Display port uses differential pairs and has very tight timings which means the length of the wires matters. Signals traveling on shorter wires will arrive just before signals traveling on longer wires. This is enough to drive one of the channels out of phase from the others. Depending on the severity you will get artifacting like you exhibited or the screen won't even turn on. I had to lengthen the two wires I cut and repaired to closely match the other 3 channels. The tolerances are very tight - I got mine to within 1mm and that cleared up the artifacting.

 

Thank you guys for answering me! Appreciate it, really!
Yes, I messed up with wires... Do you think, @aarpcard, if I solder a little piece of wire I can adjust it? Or better taking new cable?
Thanks!

 

That's what I did and it worked out. You just have to make sure the lengths of all 4 twisted pairs are pretty near identical. Also, if you are soldering wires to extend a twisted pair, use the same length of wire for each side of the pair. Not doing so will likely mess up the differential signalling.

 

On my cable the twisted pairs are all within a few mm of each other in length. I have the same number of solder points per line (one), but the solder points are at different points.

Making sure all wire was shielded was 100% necessary. Before I added the aluminum tape I would have periodic function like you have.

 

Ok, going to buy another cable, this one is not good anymore.

 

If you'd like to share a picture of it I can offer suggestions on how to solder it. My cable is currently two different cables spliced together.

 

Ok guys, thank all of you now I have 4k panel in my old p370em. As you guys said the flickering was due to different length wires. Resoldered and no more flicker! Running Mojave OS!
Thanks!