I suggest that you do one upgrade at a time.
 
In terms of the RAM, you max out at 512 mb of RAM. You need to consult the manual to see what configuration that you need. I also suggest that you try a supplier's memory configuration tool to see what is compatible with the motherboard. It will support PC 133 ram, but in certain configurations. Again, consult the resources available to you, the users manual and memory configuration tools that most memory sites have.
 
If you use more than one stick of ram in your configuration, make sure that they are exactly the same make and model sticks.
 
The video card needs to be an AGP 4X/8X card. You did not state what watt power supply that you have, which may make a difference. An example of a card that should work is here.
 
Look at the specifications tab.
 
Do a google search on your board and read what they suggest. An example is here.

i did a research and i think in the manual that 512sdram pc133 should work but the problem that in the AGP aperature Size the maximum size allowed is 128 is that mean that it doesn't support a 256 graphic chipset (like the 5500)??

I was looking at the ECS support page for data on supported video cards, but did not find any information. Often maufacturer sites will post cards that work on specific motherbords, which takes out some of the guesswork in choosing a video card for motherboards.
 
Anyway, look at this article that explains AGP aperture, as does this post.
 
BTW, make sure to use good quality memory, since memory should be very inexpensive for your system.

thank you for help

another question do you think that it is useless to buy a 256Mb graphic chipset because my processor is amd 750MHZ... and the games that require 256Mb graphic chipset they require more than 1.5GHZ in processor ?? so i have just to buy a 128Mb graphic chipset???

any answer????