memory upgrade

I am in the process of upgrading my memory to 512K, but I have been told that it is crucial to match my memory sticks (RIMM) to my video cards nanoseconds (pny ti 200), is this true? I was also told that the pny upgrade memory modules that i purchased were garbage, why would this person make such a claim? (if known)
I have a dell optiplex GX300, intel piii 733mhz 820 chipset,
256k rdram, pny gforce 3 ti 200, sound blaster audigy platinum, hp 12x max dvd-rom, plextor 12/10/32s cd-rw, adaptech 2930u scsi controller, 20/48x ide cxd-rom, dell p991 19" trinitron ( if known please identify the proper motorola or equivelent pair of 256k rimms)

om sorry, but whoever told you that is stupid, the best ram out ther for your computer is PC800 Samsung, you will need to buy two of them as RDRAM comes in pairs..