Visipro 256MB DDR2 PC5300 Memory Card

Just before my hubby and I got married, we had prepared for anything, including a PC for our new house. My brother, who was selling computer stuffs at that time, helped us in deciding the specifications we need for our new PC. One of them was deciding the memory card for the PC. He recommended this memory card, Visipro 256MB. Its a DDR2 memory card and intended for PC5300. Im not a techie so Im not quite familiar with tech terms, so I only write what I know about this memory card here. What I like about it, like my brother said, that it comes with a lifetime warranty. We decided to take the 256MB capacity because it was cheap (while we had limited budget at that time as a newly wed.. lol..). This memory card is still working well when we remove it. We have the 1GB now, and we had put these two together, but as a result, our computer was working slower with these two running, and as our service guy advised, we removed the 256MB, and now were working with the 1GB instead. We still dont know about what to do with this 256MB card. Were planning to sell it as secondhand item, but dont know if this is still worth any money.