ram

Here is a link if you have Win 98.
http://support.microsoft.com/default.aspx?scid=kb;en-us;253912&Product=w98

Remove any spaces

What does the BIOS read?

If the BIOS only sees 512MB there are 2 possible causes:

1. Your motherboard is limited to 512MB per memory slot.
This is VERY common on motherboards designs that are over 2 years old.

2. Your motherboard cannot handle the chip density on the DIMM.
Memory technology changes constantly.
Many motherboards cannot see all the RAM on the newest quad density DIMMs.

As a side note:
Windows 95, 98, and Me can have serious problems with more than 511MB of RAM installed.
The "benchmark" performance numbers actually start to decline when you have more than 196MB of RAM.

Chas