The physical differences between the types of DDR memory with DDR2 type the first is the type of memory chip used. In DDR type memory, the memory chip (IC) used on board is a type of memory module is the TSOP (Thin Small-Outline packege). The shape is square panjag with the legs on the left and right. Rarely DDR memory modules that use the type of memory chip BGA.
At DDR2 type memory, the type of memory chip used is a type of BGA (Ball Grid Away). The form there are four long Persei, those that are square. However, unlike type TSOP memory chips, the legs on the memory type BGA invisible because it is located directly under the chip and board and directly plugged into the memory modules.
Other physical differences that can be seen by naked eye at the notch is available on board memory aka the golden finger connector on the motherboard memory slot. In the type of DDR2 memory, this notch is a little more to the middle board memory module, while the DDR memory, this notch located slightly to the right side.
Last physical differences that can be seen easily is the number of pins used. Pin DDR memory has as many as 184 units (92-pin on each side), while the DDR2 memory type has a smaller pin and a solid amount is 240 pieces (120-pin on each side).
In terms of speed, memory type DDR2 is the lowest that has a clock speed of 200MHz (DDR2 400 or PC-3200), while the DDR type memory that has a clock speed is 100MHz (DDR 200 or PC-1600). Highest DDR memory types supported officially by JEDEC (Joint Electron divice Engineering Council) or a standardization body electronics and semiconductor industry is DDR 400 (PC-3200) DDR2 memory while it's been listed as DDR2 memory standard is DDR2 400 (PC-3200 ), DDR2 533 (PC-4300), DDR2 667 (PC-5300) and DDR2 800 (PC-6400).
In terms of performance, the clock speed is the same, the system uses DDR memory types usually have similar performance to systems using DDR2 memory. In many cases, even performance DDR memory is better than DDR2. This is possible because the latency and DDR memory timing is better than DDR2 memory. But again. Memory type DDR nothing is produced with speeds in excess of 600MHz, while DDR2 is still pegged at kcepatan bsa far above it. Currently there are more new variants of RAM memory, the DDR3 which has a clock speed greater than DDR2.