Half the product specification's write speed, X300

I am less than half the 470mb/s write speed as per specifications:  http://www.sandisk.co.uk/products/ssd/sata/x300/

I have this board:  http://www.gigabyte.com/products/product-page.aspx?pid=4953#sp
with bios RAID rom
using iRST driver, 13.2, & 13.6 all give similar results.

I am on the latest official F5 bios for the Gigabyte Z79X Gaming 5.

I tried to flash via DOS but I was not sure if the bios update was even on the USB stick.  I went to the dashboard and after watching a video on how to update the firmware I expected to download a file but it autoflashed in windows.  It worked but I was trying to flash via DOS.  I have a picture of the error the BIOS flash utility was giving me but its still on my phone atm.

Is the X300 a retail product? 

Model String: SanDisk SD7SB6S128G1122
Serial Number: 144646404198
Maximum LBA: 250069680
World Wide Name: 5001B44CB92DF466


i dont think that the X300 drive is a ‘‘retail’’ drive in that matter and in most cases its already build in into a computer by the manufacturer. according the speed you get with the drive i would suggest to try the SSD alone without the RAID configuration to see the actuall speed of the ssd itself.

so remove it from the RAID system and test it standalone with the speed test.


The x300 is not part of a raid array, its got 2 partitions and one contains windows 7 sp1.  There are 4 other hard drives and an optical drive.

Also my Sandisk extreme usb 3.0 has 600 on power cycle counts according to SMART, removed it till I need it again.

BTW I think there should be a message like “awaiting moderator approval” because after I started this thread I thought my post had just disappeared, only found it again as I had a tab open with it.

Hi! Sorry for my bad english (I am brazilian). This SSD is a OEM model, is a “UltraII - derived” (TLC, nCache 2.0). See this japanese review: http://reviewdays.com/archives/50000 In a AS SSD image, the write speed is below… I am suppose nCache in X300 is thin (SanDisk don’t talk about size), and is flooded fast. TLC is a type of NAND when offers low write speeds. I have one SanDisk X300 128GB, and reaches 516MB/s (read) and 477MB/s (write) on 500MB test in CrystalDiskMark, and same results of your SSD in 1000MB test. My computer is a Dell Latitude E6320, ACHI mode, no IRST installed. Test your X300 (128GB ou 256GB?) with CrystalDiskMark 500MB test, and if possible, post image here. Thanks.