I have built a brand new pc last week and I have a toshiba 1TB harddrive and 120gb Adata SSD for the OS/Drivers in my pc. After doing a fresh install of Windows 10 Anniversary, I ran some benchmarks for the hard drives using CrystalMark.

Everytime I perform a Windows reset aka fresh install of the OS.

The ADATA SSD is getting great speeds around 547 Read and 450 Write.
The Toshiba HDD is also getting great speeds around 199 read and 196 Write.

But after I install the respective motherboard drivers using the driver disk, download msi gaming app and auto windows cumulative updates via the internet everything just starts going south.

The SSD speed stays the same but my Toshiba hard drive speed falls to a mere 60 read and 60 write. As a result copying files from my Toshiba HDD to an External WD Passport Ultra over USB 3 gets me transfer rate of only 60mbps where as before the update, it stays around 100-103mbps.

I cant figure out what is causing the drastic fall in transfer/hdd speeds, what driver is causing it and how to solve it? Anyhelp will be really appreciated. If you need any further info please let me know, I really want to learn what is causing this and hopefully solve it.

Other Details:

Motherboard: ASUS Maximus Forumula VIII (latest Bios)
Ram: G skillz 2400mhz 16gb
AHCI enabled in Bios by default.
Virtual memory is auto managed by windows