I am going to replace my DVDCDRW Combo drive. Which one should I go for ? DVD Writer or Combo Drive. What is the price difference? Also How much a 512 MB DDR RAM costs. My system is AMD 2000+ Asus A7NVM motherboard 256 MB DDR RAM, AGP 4X slot, 40 GB HDD. If I add a graphics card like Geforce 5700 or Geforce 6200, will there be graphics improvement for the money I spend? I am not going to use it for heavy gaming. I just want graphics improvement on appications and some games like NFS UG2 etc. Also can i play upcoming games on low mid settings on these cards?.