Problem with Thinkpad 760XD

[BovineMage]

The story is that I was going to use Sbootmgr to allow me to boot with the CD-ROM drive, and from there, install Windows 98 SE. It boots into sbootmgr just fine, however after 2-3 seconds, the computer just randomly shuts down, and after that, whenever I try to use the power switch to turn the laptop back on, it beeps twice at me and doesn't turn on. The middle LED on the back of the computer (the one with the weird looking "V" inscribed within a circle) stays on. I tried unplugging and replugging the power cord into the computer several times, with the same outcome; BTW I also have no internal battery within the laptop, but I didn't think it should matter as long as it's plugged into an AC adaptor.

Any suggestions?

- Bovine Mage

Update: I tried booting up with Sbootmgr again, a Windows 98 SE boot disk (with CD-ROM support), and a DOS 6.22 install disk, and only the DOS 6.22 install disk works. Still have no idea to what's affecting my 760XD, but I'll keep you guys posted.

[Unknown_K]

There is a post on this site somewhere talking about the little plastic finger that fits into the inside of the keyboard (tells the machine when you have the keyboard off and to go to standby) is broken. So the machines starts to boot and then shuts down. I had the same problem in a 760ED, it would start to boot from a floppy and then do the same thing you said, only way to get it to start again was to remove the power cord (no battery installed).

[BovineMage]

Welllll.... That does explain a few things. The LCD assembly that I have does have a broken finger thing like you said (the standby switch); I just didn't think that would cause any trouble until now. I do have an interface cable that does still have the finger, but that means I have to reopen everything (I just replace a bad LCD panel on this very same 760XD) and rip that stupid cable out and replace it. Man, what a day.

Murphy's Law strikes again.

- Bovine Mage

[Unknown_K]

So that was it then?

[BovineMage]

So that was it then?

I know I have a broken standby switch on the LCD interface cable and the symbol with the weird V shape in it is the older standby symbol, but I didn't have the time today to switch out the interface cable out of the LCD Assembly, so I don't know if it's the actual cause of the problems yet. However, it's still on my DDx list of problems.

- Bovine Mage

[BovineMage]

Update:

I got around to replacing the cable on my LCD screen, so it now has the finger switch on it again. However, when I went in and tried to boot to the disk again, it turned off yet again! So, now I'm a little stumped. The only thing I could think of is the system board, but it checks out in the diagnostic test in BIOS, so I have no idea to what could be going on.

- Bovine Mage

[Unknown_K]

I was refering to the switch in the underside of the keyboard activated by a finger in the plastic of the bottom case when the keyboard is closed.

[BovineMage]

I think I got that switch problem under control, mainly by switching out the system board. However, yet another problem has surfaced: The CD-ROM drive (x6 drive; FRU 82H8850) is unable to read any CDR/CDRW CDs that I make, but it can still read some of ther commerical CDs that I put it, especially from that time era.

Is this a problem with the firmware on the computer, or is it a problem more with CD drive itself being unable to read such CDs? If so, does anybody have a solution to get around this?

- Bovine Mage

[Robbyrobot]

some of ther commerical CDs ??

I'd say there are two possibilities: dirty lens (try gently cleaning it with a Q-Tip soaked in isopropyl alcohol) or the lens is misaligned and there's no real way to go except to replace the drive.

Some drives have been known to have problems with CDRW discs and - at least in the past - with home-burned CDRs, but I've never personally had any problems with the latter, regardless of the computer - from a 760EL to a T42p. My guess is that a software problem is unlikely, although I can't totally exclude it.

[BovineMage]

I'd say there are two possibilities: dirty lens (try gently cleaning it with a Q-Tip soaked in isopropyl alcohol) or the lens is misaligned and there's no real way to go except to replace the drive.

Some drives have been known to have problems with CDRW discs and - at least in the past - with home-burned CDRs, but I've never personally had any problems with the latter, regardless of the computer - from a 760EL to a T42p. My guess is that a software problem is unlikely, although I can't totally exclude it.

I'll try some of your suggestions, and as for "some commercial CD-ROMs," I mean that it read some game CDs fine, and it read another like an audio CD... Strange.

I also found from different online resources and a friend that older CD drives from this time period are unable to read CDRs at all, due to the specs (According to Wikipedia, supposedly CD drives with X8 or higher are guaranteed to read CD-R and CD-RWs).

I'm currently bypassing all this bunk with a PCMCIA X24 CD drive that reads CD-Rs just fine, but I can't seem to use it at boot up, to install an OS. Any suggestions?

[SMA]

Once upon a time, CDR's came with a rated capacity of 650 MB. Later came the 700 MB CDR's.
Some very old CD-ROM drives cannot move their heads far enough to read the 700 MB ones.

[Unknown_K]

The data is written from the inside to the outside so even if you had a drive that cannot read 700MB CDs that would only be a problem on the edge.

I have a 6x (hitachi?) CDROM in my 760CD and it doesn't like reading mosts CDs, you can hear it trying to read them over and over. I cleaned the laser but I think it is just the laser losing the ability to read data (drift in components or something). Sooner or later it will get replaced.

Generally anything over 2X speed tends to read CDR, the earlier drives were made before CDR was available and cannot deal with the lower reflectivity of that media.

[Robbyrobot]

I'm currently bypassing all this bunk with a PCMCIA X24 CD drive that reads CD-Rs just fine, but I can't seem to use it at boot up, to install an OS. Any suggestions?

Try Smart Boot Manager. Boot it with a diskette and then see if the PMCMIA drive is recognized.