Can I Use Ddr2 In Ddr Slot

However, my other PCcould sure use some ram, but it has PC5600 (or thereabouts speed) DDR2. The slots are the same, but is there any compatibility, or is it unworkable?As of now i could still sell these sticks, as they're still sealed in the plastic. I would hate to open them up for nothing. All new versions of DDR RAM are not compatible with the earlier or later RAM. This means that the DDR2, DDR3, DDR4 memory module will not be compatible or fit in any slot in the DDR or DDR1 slot of the motherboard. DDR2: DDR2 stands for Double Data Rate version 2 It is the second version of DDR memory. This version of RAM was developed to. Lets discuss the difference between DDR & GDDR memory & can a GDDR5 graphics card be used with a DDR2 or DDR3 RAM motherboard in detail. This is one of the q.

Slot

Can I Use Ddr2 In Ddr3 Slot

Use

Can I Use Ddr2 In Ddr Slot Machines

OK! I am a noob at this!
I am running XP Pro 32-bit. I want to replace the Video Card. Nothing great or expensive...just a decent one. It for a friend (senior, that is why XP). I just got him a Dell Vostro 200 slim, added a 1TB HD and installed all drivers and XP. Please let me know 3 things:
1. Does ddr2 or ddr3 matter on the video card..is one better to run on XP
2. 64-bit or 32-bit. I assume 64 will run on 32-bit XP
3. Any suggestions on the card or where to buy (PCI Express 2.0X16)
Thanks! Ynot