-> I took advantage of the current heavy rebating on
-> SDRAM DIMMs and now have a 128MD SDRAM by K'Byte and
-> another 128MB by Kingstone and another 128MB by PNY
-> (you probably are aware they only allow one rebate
-> to each buyer 8-(

-> But when I tried installing any pair of them in place
-> of the pair of original 64MBs in my CompUSA Work Series
-> 533 Celetron system, with its Win98se O/S; the total RAM
-> that is indicated when I click my rodent on the Start menu
-> /Settings/Control Panel/System is only 191MB instead of the anticipated
-> 256MB I can manage on my Systemax Tiger 970553 or IBM Aptiva 2153
-> systems.

-> What foreplay can I use to make my CompUSA as compliant please?

Nothing really except trade one of the sticks for one that matches one
of the ones you already have. OF course you wil have to pay Full
Price to do that. I never advize mixing RAM. It leads to situations like
you have.  I would try to match the Kingston. 
 Some MB's are picky what ram they can use.
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