T42 Sec. Chip error

[Xelmon]

First of all, thank you for the quick activation of my account! Onto business...

Several months ago my T42 developed the "4 beep 4 times" error, which then led to the security chip error on the IBM TRO.
FreeGeek, the local techplace, said that "problem exists, no fix that they know of..." and then summer was over, and I had no time, until now.

I did some research and stumbled upon the countless references that "it can be turned off" - always off, "it can be resoldered" - not the video issue described, and so forth.
I also found several posts here talking about it, but none of them got resolved to any degree.

So here it is... Can it be fixed? ... If yes, what do I have to do? ... If no -afraid to ask- how much is it going to run for a new board?

It's already in pieces, more then willing to give it a shot and see where I get with it.

[Xelmon]

5-day bump.

Anyone?

[ajkula66]

Welcome to the forum!

You can remove the chip and try to clean it with eraser, then re-insert it. If that doesn't work, you need a new planar, which can run you anywhere from $100 to $200 depending on a variety of factors.

Good luck.

[Xelmon]

Thank you, appreciate the response. I saw the price for some of the boards at diff. places, thankfully my needs hit the "cheaper" end.

Now, 2 things come to mind after your instructions.
1, Is the SC correctly shown in the manual (ThinkPad Computer Hardware Maint. Man, Feb 06, for T42 board)?
2, If it is the correct chip, how would it help the chip to take an eraser to it, since I have to de/re-solder it when it's all said and done?

[bananaman]

PROM eraser.

[Xelmon]

PROM eraser.

I'm totally lost as to what that means. Please explain?

[rkawakami]

I think this exchange is getting a little bit lost... When I read George's advice about using an "eraser", I envisioned the security chip on a small PC board which plugs into the motherboard (ala, in a T23 system). Using the eraser, you would rub (clean) the electrical contacts on the connector, hoping that all you have is a bad/dirty contact. Now that I look at the T4x HMM, it says that the security chip is embedded on the motherboard. What that actually means, I don't know (none of my T41 systems are completely disassembled at the moment). If it's like the ones I've seen on the T23, then you can unplug it, clean the contacts and re-install it. However, if by "embedded" that means soldered, then you wouldn't be able to clean it with an eraser.

A "PROM (programmable, read-only memory) eraser" is a machine/technique which is able to completely reset (i.e., erase) the contents of some programmable memories. The method used varies between exposure to ultraviolet light for a period of time (for an EPROM; electrically PROM) or sending electrical commands to the part (EEPROM; electrically erasable PROM or Flash memory). Since the security chip is supposed to be resettable from within BIOS, it must use EEPROM/Flash technology. In either case, I'd say that would neutralize the security chip and you would lose any passwords/data that has been stored using that system.

ref: http://www.thinkwiki.org/wiki/Embedded_ ... _Subsystem

edit: Never mind about the soldered vs. non-soldered item. I didn't read far enough into the HMM. The T42 motherboards are supposed to have the security chip soldered to the board.

[Xelmon]

@ rkawakami:

Ah, that's what cause the confusion. I could care less about my settings if a reset solves my problem, however, I'm not sure it will.

The actual error is as follows;
The T42 sometimes works fine, sometimes doesn't. When it doesn't, it doesn't boot up, and hangs at the IBM logo.
When it does boot, if I tap/bump it a bit harder, the machine hangs up, no response. After a reset, I get 4 x 4 beeps, which is "Mobo (Security chip)".

[rkawakami]

Bumping the system to either cause or "fix" a problem seems to me to be a question of a loose device. Most likely there's a part which is not totally soldered down to the board. It could be the security chip itself, or one of the many other parts on the motherboard. I've seen several T23 systems with problems like that, but they didn't throw the security chip beep code. The best advice I can give would be to run the PC Doctor for DOS diagnostic program on the system, putting at least the CPU/Coprocessor and Systemboard tests into a loop. Download the program from here:

http://www-307.ibm.com/pc/support/site. ... MIGR-56222

Boot the system and when you have selected the appropriate test from the Diagnostics menu, press the F2 key and change the "Set loop count" value from 1 to something like 20. That will make the program repeat the test that many times. This gives you some time to physically move/bump/flex the system around and see if it fails any particular test or causes the system to hang.

[Xelmon]

Thanks, will do sometimes Thursday.