Here are some of the differences between DDR1 and DDR2 Memory :
Clock Rate and Bandwidth
DDR1 usually have a clock rate below 400 MHz with a bandwidth below 3200 MB/sec (marked with the name of the PC) and is generally divided into DDR PC3200 (400MHz clock), PC2700 (333 MHz clock) and PC2100 (266 Mhz clock).
While DDR2 has a higher clock rate and bandwidth ranging from DDR2 PC4200 (533MHz clock), PC5300 (667MHz clock), PC6400 (800MHz clock). There’s even a PC8000.
Numbers of Pin
The number of pins for DDR1 fewer than the number of pins on the DDR2. The position of “crack” buffer is also different.
Price
Now that DDR2 prices slightly cheaper than DDR1 because it has been mass produced. The DDR2 should be installed on the motherboard (in this case over to the chipset) that supports DDR2 and DDR1 apply also to be installed on motherboards that support DDR1. Motherboard that produced in 2006 commonly support DDR2. Then about the clock, better to buy the same clock rate as a motherboard supported, to make it faster (no decrease in rate).
DDR1 and DDR2 memory can only be installed in accordance slot found on motherboards that support from each of these memory. The easiest way to know the difference between DDR1 and DDR2 slots are removing one of the memory, then read the note on the sticker. And about the number of pieces. Not everything is so rich, the dual channel memory that usually are sold in pair and more expensive (performance class), and for the value class is usually not guaranteed dual channel conectivity.
