What's the difference between SDRAM and DDR2 RAM?

I want to purchase more RAM for my desktop but not sure what the difference is between the two. Is in that any major difference?

What's the difference between SDRAM and DDR2 RAM?

DDR2 is SDRAM but runs near the second version of Double Data Rate. Therefore DDR2 SDRAM is much faster but also more expensive.
its just about speed...ddr2 is much faster
It depends on your motherboard, which type of RAM it supports, if your PC is old consequently it will support only SDRAM and not DDR2.

So since you buy new push make sure that your motherboard support it. Before buying check near shopkeeper giving configuration of your PC and he will suggest you the correct RAM for your PC.
There's not much difference between the two RAM'S.

SDRAM has 168 pins on it, it's speed vary from 66mhz to 133mhz and size varies from 32mb to 512 mb.

DDR2 RAM have 184 pins on it, its speed is 233mhz,and size varies from 64mb to 1gb. so u singular look which one is suitable for ur pc n which one can u afford.
There are copious different way between SDRam and DDRam

1. Ram slot

2. speed

3. pin configure

4.memory size
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