Why is that the write speed of DDR SDRAM are faster than the DDR2
Hello, I have two different types of hardware, one with DDR SDRAM and another DDR2, i tested them with bw_mem tool for write bandwidths, seems that at higher writes of >512kbytes the DDR is faster than the DDR2(more than 40%). But when compared to reads, DDR is slower (more than 50%). I couldn't find any reference that explains why. AFAIK, the DDR2 works double the faster rate than the DDR. any ideas? Thanks,
these are tradeoff between DDR2 (for higher speed, but higher read latencies) vs DDR (lower speed + read latencies). so if u make the bus speed the same for both, then DDR2's higher latencies will make it slower than DDR. http://www.diffen.com/difference/DDR_vs_DDR2 and a technical comparison charts in numbers: http://www.freescale.com/webapp/sps/site/overview.jsp?code=784_LPBB_DDR On Mon, Jun 3, 2013 at 2:39 PM, devendra.aaru <devendra.aaru@gmail.com>wrote:
Hello,
I have two different types of hardware, one with DDR SDRAM and another DDR2, i tested them with bw_mem tool for write bandwidths, seems that at higher writes of >512kbytes the DDR is faster than the DDR2(more than 40%). But when compared to reads, DDR is slower (more than 50%). I couldn't find any reference that explains why. AFAIK, the DDR2 works double the faster rate than the DDR.
any ideas?
Thanks,
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