Question about RAM

[*old-guy*]

Is it possible that a Mac laptop could show 768 mb of SDRAM when you click on the apple at top left and then "About this Mac" and yet only be capable of using a smaller amount of the installed RAM.
The reason I ask is that my laptop had 2 memory sticks installed. A 128 pc100 and a 256 pc100. This showed up as 384 mb in "About this Mac".
I removed the 256 stick from the top slot and replaced it with a 512 mb stick of pc133 RAM. The memory shows as 768mb and according to "About this Mac" >> Memory ... all is well.
The laptop just seems a lot slower.

ps .. I have a 512 stick of pc133 on order so this may be a moot question.

 

[abramson1111]

It's complicated...
If you're a more advanced user, check in activity monitor and compare it to your stats in System Profiler.
If you're not an advanced user, go to an apple store and make an appointment to talk to a Genius

 

[windowpain]

I may be wrong on this..but I think the pc133 ram is running at (a reduced) 100MHz because of the 256 stick.

Try just running it with the one 512mb and see if it shows any improvement.