If you are going to overclock, go for the 800 MHz RAM. If not, you really won't notice a difference between 533/667/800 MHz RAM.I am planning to buy a core 2 duo e6600 sytem with evga nforce 680i motherbaord
i want to buy 2gb ram, but im unable to decide what speed ram should be...
can my system make full use of the 2gb 800mhz ddr2 ram?
wont the gaming experience be affected if i have lower ram speed??If you are going to overclock, go for the 800 MHz RAM. If not, you really won't notice a difference between 533/667/800 MHz RAM.
So it actually doesnt make sense to go for RAM higher than 533Mhz unless yur overclocking??The reason I said anything faster than a dual channel pair of DDR2 533 RAM is because of latencies. I was reading some benchmarks, and a single stick of 667 MHz RAM with a latency of 5 had almost the exact same bandwidth as a single stick of 533 MHz RAM with a latency of 4. You can get reduced latency RAM, but it will cost almost $100 just to bring down the latency one clock cycle, for example, from 5 to 4.
Here is some math:
The Core 2 Duo has an 8 Byte (64 bit) FSB that operates at 1066 MHz (effective). So...
8 B x 1066 MHz = 8528 MB/s, or about 8.5 GB/s bandwidth.
Now lets compare the bandwidths of two different RAM speeds, a dual channel pair of DDR2 533 RAM, and a pair of DDR2 800 RAM. If you have a dual channel 16 Byte (128 bit) DDR2 533 MHz (effective) setup...
16 B x 533 MHz = 8528 MB/s, or about 8.5 GB/s bandwidth.
You can see it is equal to the FSB, so your FSBRAM ratio is 1:1. This is good, since the one component that has to be fast enough to keep up with the RAM, CPU, and rest of the system is the FSB. But if you have a dual channel 16 Byte (128 bit) pair of DDR2 800 MHz (effective) RAM...
16 B x 800 MHz = 12800 MB/s, or 12.8 GB/s bandwidth.
With the DDR2 800 RAM, the bandwidth of the RAM exceeds the bandwidth of the FSB, and the extra speed of the RAM is wasted. Since the majority of the FSB in Intel CPUs is used for memory access, having RAM faster than the FSB is pointless.
Now even when taking latency into effect, it still wouldn't be worth it, because, especially when gaming, the FSB is still used for other things, like communication with the GPU. This will mostly compensate for the fact that the RAM will be slower due to the latency. Thus, a dual channel pair of DDR2 533 RAM with a CAS latency of 3 would be a perfect match for a Core 2 Duo.
Onto overclocking. Basically, if you have RAM slower than the memory bus, then you will encounter stability issues when trying to overclock by increasing the FSB. The E6300, E6400, E6600, and E6700 have locked multipliers, so you will have to increase the FSB to overclock, however, I believe that the X6800 had an unlocked multiplier, so you could simply increase that and increase the CPU speed without affecting the other components..