Thank you everyone who has contributed your knowledge to help me sorted out my problem.
After having lots of different kind of experimentation, from plug/unplug the PRAM, replace and insert back the battery and optical drive, pressing the power buttom lots of times, pressing the reset buttom, the list goes on.
Finally, today after work, I decided to bring out some courage and press hardly the board where the RAM is. After inserted hardly, try to pull out, as i remembered, when i pull the RAM out last time, it was quite difficult.
After putting it back, inserted the battery back and finally heard the sounds of the machine. Press the power buttom, and "bong" the pretty sound of MAC comes out!!! I miss the sound!!!
Just to let you know my current situation, i am running a MAC OS 10.4.11 (the latest i can use at PISMO), with 384 RAM and a 160GB Harddisk, since the maximum capacity of my PISMO supports is only 128GB, before i install the OS, i split it into two drives. One with 110GB and the rest as an ordinary back up disk for future use.
I am thinking if i can make it to 320GB and maybe split it into 3 partitions, since the PISMO cannot recognise more than 128GB.
Thanks everyone!!!
PS- I am using my PISMO G3 to type this message! :)