Hello! Just bought a Lenovo ideapad y510p and it comes with 1TB HDD and 24G SSD. I'm wondering if there is enough space on the SSD to put it as the bootdrive and using the 1TB only for storage. It all depends of how much space does Windows 8 takes I guess?
Smallest SSD I have used for Windows 7 was a 30gb Kaser drive. It was workable as an OS drive, and with regular updating left me with about 3gb of useable space on the disk. I did not experience any performance loss (to my knowledge) but it meant that I could not install any applications outside the core Windows 7 applications.
I would not recommend a 24gb SSD for a boot drive. Any performance gains you could have versus whatever drive you have in the laptop currently would be lost by having little free space for normal disk operations, and you would definitely not be able to install any applications to it. Invest a little more and get something larger.