Thinkpads Forum

I have had this laptop for a few years now, though I didn't buy it new. It has always had what I thought was a slightly dim display. Plenty bright for indoor use, but in sunlight, or even in a car during the day, I could hardly read the display. Anyway, it didn't get much use until this year, when I've been using it daily.

I have not noticed any decrease in display brightness, nor have I seen any hint of the red discoloration that I've read about many seeing when the CCFL is going bad. Then a couple of days ago, as I was installing some new software and software updates that required a few computer restarts, I noticed the display flickered a little before the Windows desktop appeared. But was stable after Windows loaded. Then on the next boot, the Windows desktop flickered a few times, and then the display went almost black (I thought it was totally black, but I re-booted and could just make out the Windows splash screen when it came up). Now, everytime I boot the display is totally black. Using an external monitor, I have determined that everything else is working OK.

So what do you guys think? Bad CCFL lamp? Should I attemp to replace it? Or, bad inverter board?

This machine is all the laptop I need, so I'd like to get it working again. If it is not going to cost too much, that is.

Thanks for the help.
Neil

Neil wrote:So what do you guys think? Bad CCFL lamp? Should I attemp to replace it? Or, bad inverter board?

My suggestion would be to start with a replacement of the inverter board. Cheapest thing to repair and should be relatively easy to do (this based upon 600X and T2x experience; I've none with the 770E so download and read the hardware maintenance manual). I recently got a T23 that the seller said had a dim display. When I unboxed it and turned the system on it had NO backlight. A $7 inverter board cured the problem, although the lamp does start reddish but turns white within 30 seconds or so.

Can you recommend a good source for Thinkpad parts? So far all I've found is refurbished inverters for $35, and CCFL for $35 also. New inverters look to be well over $100!

Well, my best source for TP parts is eBay. You can also try posting a wanted ad in the Marketplace forum here on thinkpads.com. Most likely you will not be getting a new unit on either site. A quick search of eBay for 770 inverters shows a recent sale at around $11 (shipping included):

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 0016297836

Note that this version is for the 13.3", Model "A" LCD panel. If you don't already have a copy of the Hardware Maintenance Manual (HMM), you can get one here:

ftp://ftp.software.ibm.com/pc/pccbbs/mo ... 7l5152.pdf

Page 124 lists the different types of inverter cards; just match up with whatever panel you have in your system.

rkawakami wrote:Well, my best source for TP parts is eBay. A quick search of eBay for 770 inverters shows a recent sale at around $11 (shipping included).

Well, I could wait for another party to list another inverter like that one, but who knows when that will happen (that auction ended over a week ago, and there are none up for auction right now). Or I could buy from a ebay store and pay $35 including shipping. Still if I can repair my Thinkpad for $35, I sure can't replace it for that.

rkawakami wrote:
If you don't already have a copy of the Hardware Maintenance Manual (HMM), get one.

Thanks for the help, and the links. Already have the HMM, though.

Anyone else have any comments on this. Sound like a bad inverter board to you?

Well, I still don't know for sure which went bad, but my best guess is the CCFL. It doesn't matter any longer anyway. I was able to pick up another 770 off ebay for less that the cost of a replacement CCFL ($24.50 delivered). It's display is brighter than my old one ever was. Plus, I now have some additional spare parts, including the second hard drive caddy I've long wanted.

I was hesitant about buying a parts computer, but turned out to be in better shape that my old one, only thing wrong with it was a missing CMOS battery.

Neil wrote:I was able to pick up another 770 off ebay for less that the cost of a replacement CCFL ($24.50 delivered).

It's sad that a complete system can be had for less than the cost of one single item inside it, huh?

Neil wrote:I was hesitant about buying a parts computer, but turned out to be in better shape that my old one, only thing wrong with it was a missing CMOS battery.

Some of my best systems have arrived with simple problems like a dead CMOS battery ($5 or so) or a hard drive that was just in need of a re-format ($0 cost). One of the last T23s I just got had both of those problems, along with a dead modem card which prevented booting. So for a few $$$ I got a T23 1.13G, 30GB drive, 256MB, with the best part: built-in 802.11b antennas!

rkawakami wrote: It's sad that a complete system can be had for less than the cost of one single item inside it, huh?

You're kidding, of course. I was going to suggest Neil shop for another 770e instead of parts. If you are going to work on PCs, it's always easier if you can swap suspect parts into a working machine. Plus, in the long run, the parts machine will be worth more than it cost .

I just bought this...

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 0025472694

Last time I needed to get a keyboard in a hurry, it cost me $35.

Funny thing about these craptops is that my parts machines keep getting adopted.