Sequential Read Performance
The 1TB BG4 achieves its 2,300 MB/s sequential speed in our test. The drive needs a little lift-off time to get there but manages to meet the spec at queue depth 4 and beyond. This is faster than the Crucial P1, Intel 660p, and Mushkin Helix-L. The Crucial and Intel both use 4-bit per cell flash. The Mushkin is the only other DRAMless SSD in the charts today.
Sequential Write Performance
The drive also achieves its 1,800 MB/s sequential write rating, and that's higher than all but the Samsung 970 EVO. The performance is remarkably high for an embedded drive.
Sustained Sequential Write Performance
Like the 3- and 4-bit SSDs, the high write performance comes from using pSLC programming to increase burst performance, but the writes don't stay high forever. The BG4 shows a couple of levels of cache. The quick burst that drops into a lower tier before reaching native TLC speeds. The large peaks and valleys on the chart lead us to believe that all data first writes to the SLC buffer before folding into the TLC. This increases endurance, but decreases consistency.