05-19-2015 02:51 PM - edited 05-19-2015 02:53 PM
Welcome to the Lenovo Community !
With a desktop, the opening of the case to add memory, add or replace a hard drive or optical drive will not void your warranty. Those hardware changes are considered consumer servicable parts by Lenovo and they can be done at any time. Your model's User Guide outlines the various hardware items you can replace as an owner. I have included a link to that guide below.
Keep in mind that the SSD drive won't be covered by your Lenovo warranty. If you ever experience problems with the SSD you would have to contact the manufacturer of that drive. In the event your E00-00 ever needs to be sent into Lenovo for service I would also make a point of removing the SSD before sending it in. That would eliminate any concerns of it getting misplaced during the service work.