What is burst chop -  Burst chop mode (BC4) is unique to DDR3 technology because of an 8n-prefetch architecture prevents a true burst 4 mode (BL4).  In BC4,   the last 4 bits of the burst are masked and there are clock savings for Readd-to-Write, select Write-to-Read, and select Write-to-Precharge transitions. However, while doing Read-to-Read or Write-to-Write transitions, the timing are treated like BL8; and there are no clock savings.

RAMpedia is a DRAM memory encyclopedia and reference tool
to help computer hardware board designers with DRAM memory subsystems.
This information is provided as a courtesy by Virtium Technology.
www.virtium.com