Hey guys.

need some help.

had some trouble with a WINDOWS 10 install to SSD.

there seems to be a problem after changing the OS from WINDOWS 10PRO to WINDOWS HOME since i didnt have a product KEY for the PRO VERSION.

there were some issues with DRIVE partitions and not being able to install.

currently, the 512GB X300 that i am using only shows 476GB CAPACITY after successfully installing WINDOWS 10 HOME.

there seems to be some hidden partition(s) that WINDOWS 10 Disk Management cannot see.

i am trying to reset the drive back to the original 512GB.

i have tried Command Prompt processes to format and clean the drives, but regardless of what i have tried, the drive will not reset back to 512GB.

i suspect these to be the SYSTEM and RECOVERY Partitions from WINDOWS 10 PRO installation.

i was told to try resetting the MBR. but not sure exactly how to do this.

i am willing to lose all data on this drive as this will be a totally clean install of WINDOWS 10.

there is nothing on the drive that i need to recover.

the goal is to get the drive back to the original 512GB capacity.

hope someone can help.



I don’t think you get what is labeled. There is a difference on how flash memory manufacturers and Operating System providers defines One Giga byte. Also some amount of it is utilized for optimizing certain features. Check below, the SanDisk knowledgebase article that clarifies it:

I hope that answers your question.


This discrepancy exists for decades - search it on the net and live with it

If you haven’t figured it out - I recommend you follow this guide (you may need to alter the Dell part if your system is different obviously). It will help you to clean your disk of any partitions. Please keep in mind, this will erase all user data. Please be careful in selecting the right disk if you have multiple in your system. .


Please refer to this KB article on SanDisk website about our capacity of storage devices:

From this article your drive’s capacity shown seems reasonable

Also let me ask you this: What is the privous capacity shown on Win 10 pro? Did you notice a capacity drop when you changed OS?

If there’s a drmatic capacity drop there maybe something wrong on the OS or on the drive.