Windows 11 is keeping up with the times by updating a decades-old means of reporting memory speed to a more accurate version. Windows 11 Insider Preview build 22635.3570 was released last week and has changed the unit of measure used for identifying DDR memory speed from MHz to MT/s (mega transfers per second). MHz has been the de facto metric used within the electronics industry since the introduction of SDRAM (Synchronous Dynamic Random Access Memory) in the early 1990s following Samsung’s mass-produced modules in 1993. Using MHz as a unit of measure for memory speed became outdated when Samsung debuted its DDR SDRAM a few years later but MHz has largely remained in use since.
Memory manufacturers have slowly been shifting to using MT/s in recent years but reportedly held onto the older standard to avoid confusion for consumers. Ironically though in doing so many of those who purchased DDR SDRAM ended up being confused anyway once they installed it in their PCs only to find that various software reported it running at half of its advertised speed but this was not an error or missadvertising. This was due to the need to understand how memory speed reporting actually worked, and also just the tip of the iceberg of why MHz needed to be replaced by MT/s.
Brief explanation for MHz to MT/s involving SDRAM>DDR SDRAM>GDDR5X
Tom’s Hardware has provided a brief history of the transition from SDRAM throughout the decades and even included mention of GDDR5X, a type of memory used in graphics cards which was introduced a number of years back. Many current graphics cards use either GDDR6/GDDR6X and even faster GDDR6X is expected to be used for upcoming generations of consumer cards with GDDR7 and newer HBM on the horizon.
- SDRAM debuts with memory operations now getting synced to the module’s clock speed at one transfer per cycle. Reported MHz could directly correlate to Mt/s so a speed of 100 Mhz could be considered the same as 100 MT/s
- DDR SDRAM debuts and provides double the data rate meaning twice the amount of transfers per cycle and thus beginning the root of confusion with MHz vs MT/s. PC users would discover their 2666 MHz might show as only 1333 MHz via software. At the time switching to MT/s could’ve helped alleviate confusion by simply advertising 2666 MT/s but MHz would remain the dominant unit of measure from DDR to DDR4.
- GDDR5X updates to QDR or Quad Data Rate making MHz even more of an inaccurate unit of measure.
MT/s or no unit of measure at all
As mentioned, memory manufacturers have already begun phasing out MHz on their labeling for newer modules with DD4, an industry-wide trend that continues to grow with the current DDR5 specs. Some actually go so far as to drop a unit of measure altogether and list a kit as DDR4-3600 or DDR5-8000 while others include MT/s in the product name. So now that the industry has shown a somewhat unified commitment to move away from using MHz as a unit of measure for reporting memory speeds it only makes sense that Windows 11 is doing the same. However, for now, this is limited to the current insider preview beta but it seems probable that Microsoft will eventually roll out this as a full-fledged update down the road but such a similar update for Windows 10 is uncertain with its EOL approaching.