Wednesday, July 8, 2009

Laptop LCD Screen Repair

You can get more use out of a laptop with a broken LCD. Here's how.

I recently got an old, broken laptop from a nice fellow off of Craigslist. Fortunately he'd just kept it around instead of throwing it away (too many toxins in electronics equipment to do that!)

The machine was in good shape, save for a broken LCD screen. Fortunately, this is a pretty easy fix. New LCD screens can be found on eBay for around $60 and on the web for a little over $100. (Seems to me this fix could remedy a broken desktop monitor's LCD screen, too.)

So, before we dive in, you may wonder: is it worth fixing a 5-10 year old PC? I say YES! I find that you can squeeze quite a bit of extra life out of your old PC or Mac, depending on how you use it. And that's a topic for a later blog post. Back to fixing...

Removing the Screen

Here's a quick overview of the repair and some important lessons learned. I went through some pain fixing this thing, so hopefully you can learn from my mistakes.

First of all, removing the screen is a question of removing the laptop's screen bezel, disconnecting the outer casing from the frame, and then removing the LCD from the frame.

On this particular model, an HP Pavillion ZE4900, two stickers and two small rubber bumpers cover screws that hold the bezel to the screen frame (see pic).


The Dell Lattitude D630 I use for work is similar. My older iBook has frame screws on the side of the housing (see picture).

On the HP and Mac, the screen frame consists of two vertical metal channels, one on each side of the screen. The LCD is screwed to the frame on the side at the four corners, but to get to those screws on the side, you have to remove four other screws that hold the frame to the outer casing.

Finding the Right Replacement Screen

For me the big challenge was finding the right LCD screen replacement part. The original was an LG Philips LP150x08(A5)(N1). I had hoped one could cross reference other manufacturer's part numbers and find an equivalent replacement, but I wasn't able to find a cross reference database.

Finding an exact replacement with the exact same OEM part number ensures a hassle free fix, but you may have to way awhile to find the part on that famous auction site, or you may have to pay more to get exactly what you want.

I suppose it is possible that you can get away with a similar model number. In this case, for example, maybe an LP150x08(A3) or LP150x08(TL)(A2) would've worked. I have no idea.

On the other hand, finding an equivalent may mean you end up buying one or more parts that don't fit. You can resell them, as I did with the WXGA screen, but you may end up being money ahead just getting an OEM replacement. However, if you feel like going through the effort of finding an equivalent replacement part, here are some tips that I learned the hard way!

Screen Dimensions and Resolution
Of course the most important thing is to ensure you get the right physical dimensions and screen resolution. A blog entry on icustompc.com explains the different types:

Standard Resolution

Typical Use
XGA (Extended
Graphics Array)
1024×768

[some 13- and 14-inch and most] 15-
and 17-inch LCD monitors
SXGA (Super XGA) 1280×1024

15- and 17-inch CRT monitors
17-and 19-inch LCD monitors
UXGA (Ultra XGA) 1600×1200

19-, 20-, 21-inch CRT monitors
20-inch LCD monitors
QXGA (Quad XGA) 2048×1536

21-inch and larger CRT monitors
WXGA (Wide XGA) 1280×800

Wide aspect 15.4-inch laptops
LCD displays
WSXGA+ (Wide SXGA plus) 1680×1050

Wide aspect 20-inch LCD monitors
WUXGA (Wide Ultra XGA) 1920×1200

Wide aspect 22-inch and larger
LCD monitors

XGA is typically what you'd find on old school standard aspect ratio screens in 13-, 14-, and 15-inch sizes, like you'd find on original Mac iBooks or this 1.5GHz Celeron Pavillion, or a Thinkpad T42, or other computers of this era.

I mistakenly bought a WXGA screen because the seller claimed it was for a ZE4900 laptop. It wasn't. I needed an XGA. Oops. Don't do that.


In some cases, the video card on your laptop may support a higher screen resolution than the OEM screen can deliver. For example, the Pavillion was perfectly happy driving the WXGA screen above, though it obviously didn't fit, physically.

Thickness and screw hole spacing is critical, too. You could try to find datasheets for other models and verify that the thickness and screw hole spacing is the same as what you have. I didn't have a lot of luck finding datasheets for LCD screens except for a pretty big collection of LCD datasheets here at beyondinfinite.com. Hope that helps in your search.

Connectors
Also make sure the connectors are the same. Count the number of pins and look at the original connector socket on the screen to be sure.



The screen I replaced had 30 pins as pictured above, but I mistakenly got another screen that only had 20 pins, pictured below. Oops. Don't do that, either.

I did find a website that sells various inexpensive adapters between different LCD screen connectors. So this is one option if you find a screen that fits physically but uses a different connector than OEM.

As far as I can tell almost all of these screens use the same power connector to deliver power from the inverter, a long, narrow printed circuit board mounted below the screen on the frame, which powers the cold cathode fluorescent lamp backlight for the LCD screen.

Installation

As all the technical manuals say, installation is the reverse of removal. :) You might want to test everything before you fully reinstall. And that's all there is to it. A nice simple, inexpensive fix.

Sure beats spending hundreds on a new laptop and you save another piece of useful electronics form the trash (not that you'd throw it away, would you?) while getting the most out of the energy spent to build the computer in the first place.

2 comments:

  1. I did find a website that sells various inexpensive adapters between different LCD screen connectors. So this is one option if you find a screen that fits physically but uses a different connector than OEM.

    http://www.electrocomputerwarehouse.com/

    ReplyDelete
  2. Hi, the rubber bumper pads you had to remove, do you have any idea if these can be purchased - I need 1 pc!!!!

    ReplyDelete