video inverter?

what is a video inverter used for a on a laptop?

In electronic terms, an inverter is a type of circuit that converts DC to AC.

In the case of a laptop's video inverter, it takes a DC voltage, converts it to the proper AC frequency, then multiplies the voltage to a value high enough to power the LCD's cold cathode backlight.

i see, thanks. just making sure it didnt have anything to do with resolution compatibility. speaking of which...

i just bought a used ibm t21. it has a native res of 1400x1050 and im wondering if i could switch it out for a plain old xga. or would the machine not accept that? also, and id really appreciate if anyone knows, there are five lights next to the power button. theyre hdd in used, etc etc. one of them is a screen with arrows in it, i suppose to adjust the screen size. but does anyone know how to access that light? i tried all the fn keys, no good. lastly, does the "thinkpad" button need drivers? mine doesnt work, but it could be that its broken.

thanks in advance to anyone who can answer.

You'd need to swap out the LCD, the lid and mounting hardware, and possibly the inverter and/or video card. If you had a service manual for your ThinkPad, you could look up the part numbers for a t21 with a different LCD and see if they're any different. A lot of service manuals are available on IBM's web site, but I didn't see one for the t21:
http://www.pc.ibm.com/us/cdt/hmm.html

Here is a page with other information about your laptop you might find helpful, though:
http://www-307.ibm.com/pc/support/si...id=MIGR-4PEM3F

If you want to swap the LCD because text is too small on-screen, you can increase the size of your screen fonts so that you can read text easily, but still get the benefits of a high-res screen. These steps may vary depending on your version of Windows and the particular video driver, but here's how I do it in Windows XP with ATI Radeon 9000 drivers:

1) Right-click a blank space on your desktop and select Properties.
2) Select the Settings tab and click the Advanced button.
3) On the General tab, change the DPI setting to 'Large Fonts' or Custom. (I used Custom on my 1400x1050 laptop and increased the fonts to something like 144%.)

The LED next to your button that looks like a screen with arrows in it is the Scroll Lock indicator.

The "ThinkPad button" could very well require drivers or application software. You can find all the necessary software on the Device Driver File Matrix.

yeah i know i can customize fonts. its just that default settings are almost always better than anything else. to me its what the hardware is optimized for. after adjusting fonts im sure everything else is still designed for smaller viewing (pictures, icons, everything). and websites only take up half the screen, while the other half is the blank background. the world isnt made for 1400x1050. i dont like putting my nose on the screen to read stuff.

i dealt with that with a previous pc. for 14.1, i absolutely love 1028x768. and 1280x1024 for anything bigger (perfect res for 19" lcd's).