Sometimes. You can research it or just put it in and test it with http://www.memtest86.com
Be sure to look into what OS you use. Windows 95/98/ME have issues past 512M
Bob
RAM in old spare computer (Pentium II, 266MHz) is marked SDRAM. I have a strip of PC100 128 MB left over from an upgrade of another box. Can I put it in the empty slot on the old Pent II?

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