Today when I wanted to pack my T23 for work and got it back from suspend mode, I noticed a high pitched humming noise, but thought nothing of it. At work I worked for a while when I noticed that the lower right corner of the screen turns black in a small area (covering the Windows clock on my SXGA+ screen). Luckily this was reversible. The backlight works, too. The corner seemed to be very hot, and there was still the bzzzzz noise. It just was barely audible because of the running aircondition, so I missed it earlier when I turned the laptop on.

What part could be causing the overheat in this place, lower right corner, where the hinge with battery/docking status LED is situated?

Well, I opended it up completely. The reason for this behavior was that the isolation of the cables of the backlight somehow was removed (maybe too brittle), resulting in sparks, a bit of molten plastic and burned cables. The high voltage cable was completely burned off. With the help of a microscope, soldering iron (and a soldering expert, thanks Eduardo , silicone and special insulating tape everything runs again. I assembled it a bit wrong, because there is now visible backlight leakage in my menu bar on the lower edge of the screen.

Before I will do this not very nice procedure again to fix the leakage (the white foil or the backlight got a bit misaligned while closing..), I wanted to get a new backlight to replace the old one. Does anyone know where I can buy one for an T23 SXGA+ display from Hitachi?

There is a sticky in the 770/600/etc. forum about replacing CCFL tubes in a 600 that references http://www.moniserv.com/ as a source for lamps. Another source is http://jkllamps.com/ . Of course there is always eBay, or you can do a web search for CCFL replacement lamps.

Let us know how it turns out as well as total cost.

Thanks, read a bit there. I just bought a backlight from lcdparts.com that they said has the right length and a connector (just for the high-voltage cable). 10 dollars for the backlight, 2 for the connector. (actually I bought two of each, just to have a backup...).

The ground just needs a long thin normal cable that I will be able to get easily, but the high voltage cable would be hard to find here (Rio), I guess.

How much did they charge for shipping? I think the sticky thread mentioned moniserv wanted $15 shipping for a $10 lamp.

The international shipping option added nothing to the total value of around 22 dollars.