What Windows version are you running and what are the rest of your system specifications?
Does your motherboard have the MOST recent BIOS version installed?
Do you have the MOST recent motherboard chipset drivers installed?
Plus, it IS Sabrent, and they are not a top tier manufacturer, of anything. All their products are primarily budget type hardware so I guess you probably need to at least somewhat take their paper specs with a grain of salt, but still maybe better than what you are seeing.
It probably is also a major factor what you are writing FROM, or if writing from memory to the drive, how fast the memory is and how much of it you have. CPU and memory speed might definitely play a role there. I'd update everything listed above as well as any other drivers on your motherboard product page and then see what shakes out.