I've been beating my head against the wall for the past two days trying to figure out what's wrong with my system. I recently bought a new 4tb storage drive and noticed very poor performance in Windows 10. I initially thought it was the drive until I decided to test it on another system(WIN 10) and in the same system in OSX(I'm using a PC that also has an OSX bootable drive). The results I'm seeing in OSX and the other system are what the drive should be gettting, but in Windows it's less than half the write speed, and one quarter the read speed. FYI, I'm on an X79 Asus system(Rampage IV Extreme). After noticing the issue, I realized all my mechanical drives are running slower than they should, but my SSDs all run at their rated speeds.

Here are some of the things I've done to try and figure out what's going on:
- Disabled Intel Raid and just ran AHCI mode - I was running RAID because I have a RAID 0 array for video editing(not boot drive)
- Tried at least 6 different RSTe (I didn't try RST 11.xx because I read that I would need to do a clean install of Windows)
- Tried matching in the Bios ROM to the RSTe by modifying my BIOS
- Tried every SATA connection on my motherboard, SATA III and SATA II - Even the ASMedia ports give me poor results
- Tried different cables
- Reformatted drives and Zeroed them out
- Disconnected any extra drives or peripherals
- Tried the Windows default driver in AHCI mode

I didn't try a clean install of Windows on this system yet since I'm hoping to avoid it. My current system runs in UEFI mode, but I've tried using CSM for boot storage when I tested different ROM module versions. I've attached 2 photos to show you the different speed results I'm getting.

OSX - http://imgur.com/rj5rTAg

WIN 10 - http://imgur.com/JQpzEqS

Edit: Here's an HD Tune test result from my girlfriend's computer with the same drive I used in the other tests. http://imgur.com/3c3VLav

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Zitat von Fernando im Beitrag #2

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@kundica:
What I cannot understand is, why you decided to use a 4 TB sized HDD instead of one of your SSDs as bootable system drive.

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Zitat von Fernando im Beitrag #4

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Have you already tried to change the SATA port, where the HDDs are connected to?

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Quick update. I did a clean install to another SSD and I'm getting the expected read/write rates on all mechanical drives. I used Nlite to remove the default Win 10 AHCI/RAID drivers and replaced it with v13.1.0.1058 since my BIOS is currently flashed to the same series.

The install that isn't working correctly is rather new(Feb) so I'm not sure how it got messed up. Perhaps it's time to install a 950 Pro as my main system drive and start over.

i have a sabertooth x79 , the board has two sata 6 Gb/s and 4 sata 3 Gb/s ...
check if you used the right ports and right cables....some are 3 or 6 Gb/s

your tests are not bad...ssd are very fast and do around 300 or 500 Mb/s .