BleepingComputer.com: DDR2

Ok i was asked a question i don't know how to answer. The question is, How does DDR2 standards work and why is it important to consider the standards when purchasing the memory? Can some one please enlighten me?

http://en.wikipedia.org/wiki/DDR2_SDRAM
is a good explanation of how DDR2 works. Typically, theres two big things to look for when choosing ram (well 3, one being quality) and they are A: speed, and B: latency. DDR2 can range anywhere from 667 mhz to 1200 mhz. typically, the faster the ram the better, but not always you also need to look at the timings (latency) the lower the timings the better. the faster the ram is, the higher the timings are, so its important to find a good balance. in fact, it may be better to purchase 1200 mhz DDR2 then 1033 mhz DDR3 due to the lower timings, however 1600 mhz DDR3 will run faster then the DDR2. I recomend to people when they want good ram to get the fastest they can afford, with the better timings. take the ram for my system-its patriot DDR2 800. (i always use Patriot ram its good quality) there were two patriot options available for DDR800-one thats timings ran at 5-5-5-18 and one that ran at 4-4-4-12. I chose the 4-4-4-12 because it would be the faster choice. :D

Also, realize that there are differences, especially with the timings, between DDR2 and DDR3. Not all motherboards accept all RAM speeds, so using DDR2-1600 on a board that goes up to DDR2-800 with the same timings is largely pointless. I also agree that that Patriot memory is very good, but there are other options out there. I've found that if memory from any company lasts through a night of Memtest without errors, chances are it will not fail.

yes DJB is right there are several brands of memory that is very good. I stick with Patriot because I find it reliable, and I see no reason to change if it works. Other good brands include (but not necessarily limited to) corsair, OCZ, Crucial, or G. Skill. :D