Sometimes wont powerup, also has an Intermittent crash, Laptop has to powerup again.

If you added another 512Mb RAM to increase the RAM to 1Gb then the new 512Mb memory stick could be incompatible with the original 512Mb or it could be faulty.
Use RAM that is same make and speed as the original RAM.
Remove both RAM and just insert the new 512Mb into your laptop and see if the laptop boots up, if not then the RAM could be faulty.

Hi - according to memory suppliers your T23 has the following memory capacity / requirements:

• IBM ThinkPad T23 maximum RAM capacity: 1GB
• Your IBM has Two (2) memory slots or sockets
• Module upgrade PIN count is: 144-PIN
• The memory speed is: SDRAM 133MHz, PC133
• The laptop DIMM type for the ThinkPad T23 is: SODIMM, SO-DIMM, Small Outline DIMM
• Non ECC

If you are meeting these requirements, you may have a defective module.

Also, according to Lenovo's page on the machine:

Memory
The system has 128MB or 256MB of memory standard and can be configured for up to 1GB of addressable memory. Memory options up to 512MB SDRAM SO DIMMs each can be added in the two available slots for memory expansion. The standard 128MB of memory is expandable up to 640MB and the 256MB of memory is expandable up to 768 MB of addressable memory with 64, 128, 256, or 512MB SO DIMMs without removing the 128MB SO DIMM that is standard in one of the internal slots for memory. For customers that need the maximum 1GB to which memory can be expanded, it is necessary to replace the 128MB or 256MB card with a 512MB card plus add another 512MB card in the extra slot. Only 133MHz DIMM memory can be used in this system. The use of 100MHz DIMM memory is not supported in the T23 systems.

This means yo can trouble shoot the 512MB modules individually by installing one of the original 128MB modules and one of the new 512MB modules (for a total system memory of 640MB). If it does not boot, try again with the other 512MB module. This will help you identify a defective module that may be preventing the machine from booting.

I hope this helps & good luck!

You can upgrade the memory to a maximum of 2 GB using either 533 Mhz or 667 Mhz modules. There are two memory slots in this notebook so you would need two 1GB modules

Hello and Welcome to FixYa!

Try re-installing your operating system (you can use System Recovery if your laptop is equipped with. But do make sure that you have all your important data back up to external mass storage media). Make sure that your laptop is virus free. If the problem still persists, I would suggest you to upgrade your Ram to a maximum of 512mb. If your system is equipped with 128 or 256mb of ram. Upgrade it to 512mb Pc2100 DDR SDRAM.

Have a nice day,

Concerned.

Since, CMOS Battery and the RAM plays very important role during post so, you may replace the CMOS Battery. If the issue persists then check if the RAM module is okay.

Furthermore, you may also replace the RAM module and try installing it into another available slot.

I assume the laptop had originally 256Mb RAM and you put 512Mb RAM in a the spare memory slot and you expected to see 768Mb of memory, is this correct? Try removing the 256Mb memory module and insert the 512Mb memory module and see if the laptop boots up with 512Mb of RAM. If it doesn't boot up then the RAM is either incompatible or faulty. Try using RAM modules from the same manufacturer.

try removing the ram and try again

Try re-seating the RAM. If that doesn't work ensure that your laptop supports the ram you bought. If the RAM you have is PC2700 and your computer only supports up to PC2500 (for example) it wont work.

Hi,
One or both of your RAMs have developed a fault. Change both RAM. After changing RAM pl format again and than try. Do not insert those faulty RAM again. Get your RAM tested by a software which is available on Microsoft site for free.
Thanks
Bhaskar

This is probably a problem with your DIMM(RAM) Did u recently install an extra RAM?If yes then remove it because the beep sound is due to the mismatch of frequency of two DIMM's. If not open your computer and check if the DIMM is loose just push it in and powerup your comp..Let me know if its fixed..