I have just bought the same laptop - quote from the seller's website "A dual-storage design with up to a 512GB PCIe® SSD and 1TB HDD gives you the perfect combination of large storage capacity and fast data read/write speeds." Ebuyer.com
The same quote is on a number of sellers' sites so they can only have got this from ASUS!! I'd post the direct links but as a new user I'm not allowed
laptopsdirect.co.uk
"A dual-storage design with up to a 512GB PCIe SSD and 1TB HDD gives you the perfect combination of large storage capacity and fast data read/write speeds. "
from Amazon
"Store more, do more ASUS A509 has a dual storage design to give you the benefits of superfast data performance and a large storage capacity. Install apps on the SSD for quicker response and loading times, and use the HDD to store large files such as movies, music libraries, and photo albums. "
I bought this because of that feature and I even confirmed with the seller what type of drive I would need. I will be sending it back!!!