SUBSIM Radio Room Forums - View Single Post - I'm considering to upgrade mu CPU. Need advice

Arclight · 04-21-09, 05:03 AM

Comes down to:
SDRAM > 1 transfer per clock
DDR > 2 transfers per clock
DDR2 > 4 transfer per clock
DDR3 > 8 transfers per clock

With each new "tech level", bandwith is doubled. Memory is about 2 things: bandwith and latency. Bandwith refers to how much data can be tranfered in a given timeframe (exampl: 1GB per second). Latency refers to how long it takes for a command to be completed. (example: data is requested by something and 80 nanoseconds later it gets it).

If a lot of small things are requested from memory, scathered over a lot of different adresses, latency is more important. If a large, continues block of data is requested, bandwith is more important. As far as I know, latency has a bigger impact on gaming performance.

CAS 4 DDR2 and CAS 8 DDR3 offer practicaly the same latency, but DDR3 offers double the bandwith (at same bus-speed). DDR3 is also more energy efficient, leading to reduced temps. DDR3 prices are now at the same level as DDR2 was at the time I bought my memory.

04-21-09, 05:03 AM	#16
Arclight Navy Seal Join Date: Jun 2008 Location: Land of windmills, tulips, wooden shoes and cheese. Lots of cheese. Posts: 8,467 Downloads: 53 Uploads: 10	Comes down to: SDRAM > 1 transfer per clock DDR > 2 transfers per clock DDR2 > 4 transfer per clock DDR3 > 8 transfers per clock With each new "tech level", bandwith is doubled. Memory is about 2 things: bandwith and latency. Bandwith refers to how much data can be tranfered in a given timeframe (exampl: 1GB per second). Latency refers to how long it takes for a command to be completed. (example: data is requested by something and 80 nanoseconds later it gets it). If a lot of small things are requested from memory, scathered over a lot of different adresses, latency is more important. If a large, continues block of data is requested, bandwith is more important. As far as I know, latency has a bigger impact on gaming performance. CAS 4 DDR2 and CAS 8 DDR3 offer practicaly the same latency, but DDR3 offers double the bandwith (at same bus-speed). DDR3 is also more energy efficient, leading to reduced temps. DDR3 prices are now at the same level as DDR2 was at the time I bought my memory. __________________ Contritium praecedit superbia.