Yes, I believe that is the case, 512MB is the max RAM that Win98 will detect, which is more than enough for 98. All the more reason to upgrade to 2K/XP!
Windows 98 works fine with more memory.
This box I'm on right now has 768MB
Over 768 you may need to limit the vcache amount through the system.ini file so it doesn't take all the availible addresses as it maps all those memory locations.
I have another system with a gig of Rambus that I had to do that to in order to dual boot into 98.
If your systems not reading all the memory, chances are it more likely a motherboard problem or one of your sticks isn't compatable with the others.
Dave
I don't think thats your problem because your system would boot and recognize the large amount of RAM without needing to change the setting. You only need to do it if you hit memory errors while in windows.
I think you will find that the "off brand" stick isn't compatable with your system.
First thing you should try is booting with it alone and see if it works.
Or, pull one of your old sticks and boot with one of each.
If your system then reads 256 instead of 512 then it's the "off brand" stick causing the problem.
Dave