Originally Posted by Majin SSJ Eric
Apparently not as this TLC Evo apparently matches the speed of the 840 Pro but at a significantly lower price...
Originally Posted by edo101
wait I thought thats what the 840 series were for. The 840 pro was for enthusiasts. I don't care if the speed matches up to the 840, how much cheaper will it be and how crappy is the controller
gonna be. Big difference between TLC and MLC
840 and 840 Pro used the same controller
(Samsung MDX), speed difference doesn't have anything to do with the quality of controller.
[First up is the upgrade to the controller. Samsung’s naming scheme from the 830 onwards has been MCX (830), MDX (840, 840 Pro) and now the MEX with the 840 Evo. This uses the same 3-core ARM Cortex R4 base, however boosted from 300 MHz in the MDX to 400 MHz in the MEX. This 33% boost in pure speed is partly responsible for the overall increase in 4K random IOPS at QD1, which rise from 7900 in the 840 to 10000 in the 840 Evo (+27%). This is in addition to firmware updates with the new controller, and that some of the functions of the system have been ported as hardware ops rather than software ops.
840 EVO uses a more advanced new controller (Samsung MEX) and more aggressive caching process and "Turbo Write" to achieve speed parity with 840 Pro.
Edited by sherlock - 7/22/13 at 11:32am
The most thought provoking announcement was TurboWrite. This is the high performance buffer inside the 840 Evo which contributes to the high write speed compared to the 840 (140 MB/s on 120GB drive with the 840, compared to 410 MB/s on the 840 Evo 120GB). Because writing to 3-bit MLC takes longer than 2-bit MLC or SLC, Samsung are using this high performance buffer in SLC mode. Then, when the drive is idle, it will pass the data on to the main drive NAND when performance is not an issue.
The amount of ‘high-performance buffer’ with the 840 Evo will depend on the model being used. Also, while the buffer is still technically 3-bit MLC, due to its use in SLC mode the amount of storage in the buffer decreases by a factor three. So in the 1TB version of the 840 Evo, which has 36 GB of buffer, in actual fact can accommodate 12 GB of writes in SLC mode before reverting to the main NAND. In the 1TB model however, TurboWrite has a minimal effect – it is in the 120GB model where Samsung are reporting the 3x increase in write speeds.
In the 120GB and 250GB models, they will have 9 GB of 3-bit MLC buffer, which will equate to 3 GB of writes. Beyond this level of writes (despite the 10GB/day oft quoted average), one would assume that the device reverts back to the former write speed – in this case perhaps closer to the 140 MB/s number from the 840, but the addition of firmware updates will go above this. However, without a drive to test it would be pure speculation, but will surely come up in the Q&A session later today, and we will update the more we know.