Windows only showing half capacity of the disk?

As most people have already answered, it might be that the SSD drive has been partitioned.  Some computer makers partition a drive and allot space to serve as the Windows Backup.  This "backup" drive is not accessible.  The other possibility is that your computer BIOS or Windows 7 does not support a 500 SSD drive.  Windows 7 operating system is ancient.  My suggestion is to see if there is an update for your current BIOS and/or upgrade to Windows 10.

Right click 'My Computer' icon and select 'manage'. In computer management, at the left pane, under 'Storage', select 'Disk Management'. It will show all drive volume disk usage. Check the 500GB SSD for it's details space usage. The exact total size for 500GB SSD should be detected as 465.66 GB in disk management under Windows 7.

May be a hidden recovery partition on the disc

Generally, it happens that the hard drive shows the wrong size to a lot of users. The main reasons for this problem are: 

- Partition deleted or lost, showing unallocated

- The hard drive, SSD, or external hard drive is with MBR style

- Files invisible 

- Virus or malware infection

Try to scan and restore all existing available data on the hard drive, SSD, or external hard drive!

Step 1: Click on “Start”, then type “Device Manager” in Search box, then hit “Enter” to open it. Step 2: Click “Disk drives” to expand the category. Right-click on the hard drive which reports wrong capacity and select “Update driver”. Step 3: Select “Search automatically for updated driver software.”

yes and , seems you have the amount mixed up  , a 500 gig uses 500 gigs total ( about 460 gigs in real calculations , 1024 byte to a kilobyte multiply it by your 500 gigs total , not the standard measure , its all to do with mathematics , and does your windows keep a copy of itself in hidden mode . remember your drive uses a different system , you windows shows free kilobytes at 1024 per kilobyte , your hard drive is straight out 500,000,000 bytes .

Well - run Computer Management and take a look to see what portion of the HD volume you allocated to the C:.  If the other half is available, the extend the disk to include the entire capacity.

go to disk manager and take a screenshot and upload the results here.

I am a bit puzzled when you say it is new - Windows 7 was discontinued 2012

disk manager software may recover the other half.  try cnet.com's downloads for free versions

Did you open up the laptop to inspect the SSD?  Did you get the exact model number off of the SSD itself?  Most likely explanation is that your computer has a 256GB SSD in it.  But you have to confirm that and take pictures if necessary.  This will probably be a warranty claim, or return the laptop for a refund...

I forgot to add...if you don't know how to open up your laptop to inspect the SSD, just search for the model number on Youtube, and there will likely be a video of somebody upgrading that computer who will show you how to open the computer...