Ibm think pad t43 /1872/bb6 i want see where is security chip laptop mainboard\

Sometimes (rarely) laptops need a bit of a kick to get them going! When confronted with this particular issue, I power off the laptop, disconnect the power supply, remove the battery and discharge any residual charge by pressing the power on switch for a couple of seconds.
Replace the battery, re-attach the power and reattempt the normal power on cycle. See it that kicks it into action!

Four cycles of four short beepsand a blank screen.Problem:----> System board (security chip)
Do you still have warranty?
Try pulling out memory sticks and putting them back in.. here is something I found. Might help.

For reseating instructions (for my T42p), I used:

http://www-307.ibm.com/pc/support/site.wss/MIGR-46513.html

http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-46515

and a video, which reminded me that there was one more screw to remove(!):

http://www-307.ibm.com/pc/support/site.wss/MIGR-50227.html

Hi
It's not difficult
You can download the service manual for your laptop, it's .pdf file, and can see all hardware details about your laptop.

Please tell us your results
Good Luck

Is it a Bios Password or a Hard Drive Password???
If a bios pass... you need to find the CMOS battery (think it's under your keyboard on that model, though not sure offhand).. Remove the battery.. Make sure battery is removed and not plugged in.. THen Hold Down The Power On Button For 30 Seconds.. Reattach the CMOS battery..
Boot Up The Laptop..
If Still Pass Locked Then You Have A Security Chip... this is embedded onto the mainboard and You would then need to replace the board (unless you know someone who can remove it and reflash it)..

Hi, If you are talking about the Boot, HDD, Bios password, then the only one way to recover it is to implement a chip on the systemboard to shorcut the protection or to contact Lenovo for a systemboard replacement. Unfortunalty, no other ways other round. Thanks and have a nice day J-

IBM Supervisor password can be removed only with a special gadget that solders to Atmel chip and reads password.
Look IBM Supervisor password removal.

If this is a bios password, then no. The password is embedded in the security chip on the motherboard. These chips are designed so that if you try to remove them without the specialized equipment, they ruin the board, I've tried. IBM can't even get around this password, and when you send it in, they replace the chip. It's cheaper to replace the motherboard than it is to have the chip replaced, considerably cheaper.

Now, if this is a Windows password, then you can either start the machine in safe mode, log in as administrator, and clear any passwords from the user accounts section in the control panel, or you can perform a system repair with your recovery or operating system disc.

This is not good. It generally indicates that the security chip on the motherboard has malfunctioned. A hard drive failure can also cause this occasionally, but mostly it's the chip. Start by trying a new hard drive, if it works, GREAT, if not then the chip has malfunctioned and locked the system. Your only option is replacing the motherboard.

Try running it without the battery. Sometimes an IBM battery can develop a short and cause this. If it still does it without the battery, I'm afraid it's the power management chip on the motherboard, and the motherboard will need to be replaced.

I've seen this once before, except there was an error code 225 that went with the hand. turned out to be an unsupported or bad memory chip. There should be on board memory on your model try taking out the memory and starting it.