A31 Gets New CPU, but "Fries" LCD

[sausage888]

I had been inspired by the tales of upgrading CPU's in A31's here on this forum, so I decided to give it a try. My A31 to be upgraded is a 2652-X7X (2652-M5U) with 1.8GHz CPU, which Intel identified as sSpec# SL6FH. I found a 2.4GHz replacement on E-Bay which was advertized as sSpec# SL6K5.

Prior to installing the new CPU, I did the latest BIOS update: 1GET41WW. No problems with the BIOS update; not sure if this matters?

I installed the new CPU without a hitch, being very careful, etc. and the new CPU worked instantly and great for a few days. Then I started to get intermittant screen flickering, which progressed into black screen shutdowns. I would wait for a few hours and try again. The last time the flickering ended with my screen going about half black, then more black around the edges, then shut down again.

Fearing that the new 2.4 Ghz CPU was causing my problems, I changed back to my old (1.8Ghz) one and had the hardest time trying to get through the BIOS correction of the CMOS system date with no screen. Actually, I could see the IBM logo very faintly if I held a bright light up to the screen, so I knew I was on the BIOS segment. It was like Helen Keller at the keyboard trying to guess what the sequence of F9's, ESC, and F10's, and my admin password were to get it to boot through to Windows XP.

Once I had Windows XP up on my "blind" laptop, I could use my other laptop to connect and everything seems to be working except for the screen being black. So now I am back to my old configuration, but have no display.

So three questions:

1. Did the 2.4 Ghz CPU cause this?

2. Did I damage the system board?

3. How do I remedy the LCD problem?

FYI: I ran PC-Doctor for Windows on the "blind" laptop and the system board and graphics card tests pass. I guess there is no real test for displays (inverters, lamps) other than visual verification.

[zone]

1. Did the 2.4 Ghz CPU cause this?

Nope. I have 2.5GHz in my A31p and many forum members did 2.6GHz upgrade without any known issues.

2. Did I damage the system board?

Not likely. To make sure connect external display on and boot system, if you have output on external display system board should be OK.

3. How do I remedy the LCD problem?

My guess is CCFL, it may be inverter but from your description (which is BTW pretty much similar to what happened with my A31p) I would suspect CCFL... I started with replacing inverter first but it seems that CCFL went south. Note that CCFL is lasting about 3 years of heavy use, so it's time to either replace display or CCFL.

FYI: I ran PC-Doctor for Windows on the "blind" laptop and the system board and graphics card tests pass. I guess there is no real test for displays (inverters, lamps) other than visual verification.

CCFL test is obviously not for an blind tester.

[sausage888]

Right! Now in retrospect, maybe it was just an unrelated coincidence, except that I never had a lick of trouble from either of my A31s. What was throwing me a curve was not being able to see to get past the BIOS screens, just listening to double beeps. Seemed like A31 was a goner.

The blind A31 is fully functional - except for the display. I can connect to it from my other laptop and it works fine. I've been reading up on display failures and will try the inverter, cable, CCFL replacements. They are all parts at or under $10 each.

I have the A31 IBM repair manual and it doesn't a thing about CCFL replacement. I wonder if the authorized TP solution is just to replace the entire LCD as a unit, rather than tinker around with pulling it apart, digging out the bulb, and soldering? You would think the repair shops would just have whole working lids around...

I guess if this is a problem particular to LCD's, then it was formerly only a laptop owner's problem. Now with desktop owners on flat screens (even our TV's, yikes!), we'll all have to learn how to do it.

[sausage888]

Just for the record, I replaced the inverter today and it did nothing. The question now is whether to tackle a CCFL replacement in the LCD I have or just buy a LCD panel?

Problem is that a lot of LCD panels for sale on E-Bay are already used. Anyone with any insight into this, please PM..

[sausage888]

As my next course of action, I opted to replace the entire LCD unit instead of monkeying around with CCFL lamps which seem to have only minimal success. Today, my display is once again working! I ordered P/N 11P8206 as a reconditioned unit from a guy on E-Bay who seems to have lots of them for around $75.00 each. They appear virtually new.

Now that I had the old LCD ready for the trashcan, I thought I would take a thorough look at it and see what it would have taken to try and replace the CCFL lamp myself. Even after carefully removing the sticky tape on both top and bottom which connects the circuitry to the frame, it is still not possible to free the LCD from the frame without removing numerous microscopic Phillips screws which hold the LCD into the frame. I don't have any tools that tiny.

After reading several instructional photo essays on CCFL replacement, my thought is... You've got to be kidding!

On the subject of the CPU replacement, I ended up putting a SL6K5 (2.4 Ghz) into both of my A31's. The other laptop had no incident.

I found this application called MobileMeter, which clocks your CPU speed and temperature, as well as the temperature of your hard drives. It is interesting to see the Intel CPU "stepping" in action, by watching the MobileMeter - both CPU's run @ 1.2 Ghz until some peek demand warrants them kicking into 2.4 Ghz mode. I guess that is to keep them cool and using less power..

I learned a lot from this experience.

[peggymac]

I just posted a question in another thread about this, and now I just saw your post. Could a person with not much technical experience replace an LCD unit?

My screen started flickering yesterday, was getting dimmer and pink in the past few weeks, and today just went black, although the display could be seen with a flashlight.

I was thinking of replacing the inverter, but that didn't solve your problem, huh? I wouldn't ever try messing with the CCFL.

Thanks!

Peggy

[phool@round]

peggymac,

It's your bulb, pink is a dead give-away. It's not too difficult to replace the screen at all. A small phillips screw driver, about 8-12 screws disconnecting some tape, the ribbon cable and inverter cable and voila' your ready to replace with new. Rinse, repeat, reboot.

[sausage888]

I ended up replacing the entire LCD unit, and yes, if you do that it is only a few screws from the sides. I got a reconditioned one from E-Bay for around $75 and that was fine.

However, since I had read a few articles on replacing CCFL's, I decided to try it on my old LCD unit by order a new bulb for around $10 and taking my old LCD apart. I am a very careful guy and good at working in small detail, but let me tell you that CCFL replacement is tricky business. The whole unit once disassembled is just paper and sheets of plastic and circuitry and all of it is sticky, sticky, sticky. The CCFL bulb is held in with some doubled-edged tape and it has to be just in a certain spot. I got it to work, but once you glue the whole mess back together, the bulb was slightly off and you can see the image of the bulb on the display, plus I somehow damaged a row of pixels. I kept the "repaired" one to have as a spare, but CCFL replacement is not for anyone but the factory.

[RWDPLZ]

...but CCFL replacement is not for anyone but the factory.

Amen. The first time I tried to replace one, I bent one of the films. The second time, the screen I'm using now, I was able to pull it off, but not after hours of frustration, and tracing a short at one end of the bulb that caused the bulb not to work (electrical tape fixed that). Now the screen works, but there are a couple 1cm by 1cm dark spots at the bottom corners of the screen.

If I get (yet another) bad backlight screen, I'm not going to bother trying to fix it