From the moment Solid-State Drives started using the “M.2” form-factor we have been recommending that buyers use either a heat spreader (for secondary storage) or a heat sink (OS and other high-stress scenarios) to help their new SSD live up to its full potential. The reason for this is simple. Not-AND (‘NAND’) transistors become (more) fragile at higher temperatures and thus have a shortened lifespan. To alleviate this, SSD controllers slow down IO requests to ‘throttle’ performance based on temperature levels. This certainly helps NAND lifespan but noticeably lower than expected performance is a legitimate concern for power-users. Concerns which have only grown with the advent of PCIe 4×4.0 based models which run hotter and stress the NAND more than their PCIe 3.0 counterparts. That is why when we heard of the Silicon Power’s XPOWER XS70 and its low, low asking price of only $130 for the 1TB variant we jumped at the chance to deep dive into what it has to offer.

On the surface, the new XS70 is pretty much par for the PCIe 4×4.0 course. It offers good performance specifications of 7,300 read and 6,800 write backed by a 1Million 4K IOPS rating. It makes use of Phison’s tri-core (3x 12nm ARM Cortex R5 with dual 28nm ‘CoXProsser 2.0’) E18 controller; enough onboard RAM to keep up with the IO demands of PCIe 4 bandwidth; uses Micron’s excellent B47R NAND. The 1TB variant (and smaller) even is single-sided for ease of real-world cooling. Then Silicon Power sprinkles in a good 5 years, with 700 TB bytes written, warranty. These are all things that we look for in a PCIe 4.0 M.2 solid state drive… as they pretty much mean it is a Phison ‘E18 reference’ design. A design that may not be perfect, but its quirks are known and easily alleviated.

intro - Silicon Power XS70 1TB Review

Unlike many others offering their own take on the standard Phison E18 reference drive, Silicon Power then ups the ante. They do so by adding in a very nice heatsink without upping the price. One that is a true heat-sink and not heat-spreader. We say this as it combines a decent amount of mass with a decent amount of surface area via cooling fins (or what Silicon Power refers to as ‘gills’ in their marketing literature). This combination is so good Silicon Promises a 40 percent reduction in temperatures compared to bare drive versions. When you mix in the fact that this combination of performance and cooling is only 10.8mm high, or ~6mm above M.2 ‘D5’ z-height restrictions, typical incompatibility concerns are minimized.

Simply stated, this combination of known good performance with potentially good to great cooling which is also not overly costly sounds like the makings of a great value. It does however beg the question on whether it actually is a good deal or just sounds like a good deal. After all, on first blush the specifications and component choices are dead ringers to NVMe SSD model’s such as XPG’s S70, MSI’s Spatium, and a whole host of other ‘reference(ish)’ E18 models. Models which all cost more than what Silicon Power is asking. So is the XZ70 a great value, or are most better off looking at the slightly more costly alternatives due to hidden cost cutting measures? Let’s find out.