The new Samsung 750 EVO is only a slightly different beast than its predecessor, the 850 EVO, but the differences are all to the good. The most salient is the speed at which it reads and writes large files. The 750 has a bit more cache, so you won’t work outside of its bounds as often—and when you do, sustained operations are a bit faster.
The icing on the cake? The 750 EVO is also less expensive than its 850 kin. The 500GB drive we tested is only $149 MSRP (and $139 on Amazon), though much of the drop has to do with the general lowering of NAND prices. The 750 EVO isn’t the cheapest SSD out there, but it was within about $15 of that distinction when this was written. And given that Samsung is very good at this SSD stuff, perhaps a slight premium is in order.
Specifications
The 750 EVO we tested is a 2.5-inch, TLC NAND-based, SATA 6Gbps SSD using the latest version of Samsung’s MGX controller. Because 3-bit TLC-NAND isn’t as fast as SLC or MLC (1-bit Single-Level/2-bit Multi-Level Cell) NAND, when written to a drive’s full capacity, three bits at at time, some portion of a drive is often used to mimic those faster NAND types. This portion of faster-acting NAND is referred to as the drive’s cache. And while it helps mitigate the potential performance lag of TLC NAND, the trade-off is that the cache reduces the amount of overall storage.
Samsung The 750 EVO could’ve been called the 860 EVO, following Samsung’s progression from 840 to 850 to... We’re not sure why Samsung backslid on the designation.
From the appearance of the dialog during a 20GB copy (shown below in the Performance section), Samsung devoted about 7GB to 8GB worth of NAND to cache. There’s also a smaller, faster 256MB DRAM cache to speed common small-file operations.
Performance
We’ve already mentioned that the 750’s performance exceeds that of the 850, but it retains a favorite trait of the 850—smooth, consistent copying. With many TLC drives, writing outside the cache creates a noticeable dip while the drive figures out what’s going on. Not with the 850 or 750. Look below at the capture from our 20GB single-file write and marvel at the magnificent steadiness while not using the cache!
Even after it exceeds the size of the cache, the 750’s performance is good for a TLC NAND-based drive. And extremely consistent.
AS SSD rated the 750 EVO as reading at 505MBps and writing at 407MBps. Of course, AS SSD writes only 10GB, so a large part of the test occurred within the cache. In our 20GB copy tests, the writing dropped off to about 310MBps and held steady there. That’s about 30MBps faster than we saw from the 850 under similar conditions—a nice improvement. While writing to the cache, we saw speeds between 400MBps and 420MBps.
This is a somewhat unfair comparison between the EVOs and the MLC-based Kingston HyperX Savage. But note how the 750 did significantly better than the 850 in the single-file write.
There are only mild differences between the 850 and the 750 when it comes to single-queue 4K operations.
Overall, the 750’s performance falls short of a top-notch MLC or SLC SSD, but subjectively, other than those times that you’re copying large amounts of data, the differences are hardly noticeable.
RAPID!
While the 750’s native performance is better than the 850’s, and smooth as butter with no additional software, Samsung does supply its RAPID interactive (with the drive) disk cache.
RAPID is enabled via Samsung’s Magician software SSD utility, is transparent to the user, and makes the apparent speed of the drive, as well as the feel of your operating system absurdly fast. The numbers you see below bear that out.
However, when copying large groups of files, operations, while somewhat faster, become distinctly choppy as the cache is exceeded. You can readily track the interaction between the drive, cache, and normal NAND in the copy dialog seen below.
With the RAPID caching software installed, the 750 EVO’s everday performance is absurd—beating the pants off Samsung’s own very-fast NVMe drive. But using main memory to cache disk writes can also lead to problems if power is removed while you’re still working.
Using the RAPID caching software is still effective, if not as much so during large copy operations.
While this 20GB file-write operation was faster with than without the RAPID caching software engaged, it was also wildly inconsistent.
Generally speaking, using RAPID is worthwhile just for the incredibly facile feel it gives your computer. However, there is a danger; should your computer lose power in the middle of a write, data may be lost or your file system corrupted. If you’re not doing anything particularly important, use RAPID. If you regularly deal with mission-critical data, don’t.
Conclusion
Samsung’s 750 EVO is the cream of the TLC-based SSD crop. It costs a bit more than the competition, but to my mind, the smooth performance is worth the extra dough. Especially as RAPID can give your computer a feel that’s otherwise only achievable with a PCIe/NVMe SSD.
My only caveat is that there are still MLC NAND-based drives available for just a few dollars more than the 750 EVO. If using RAPID is not an option for you, then those drives offer a better all-around experience.
