I have a 4 month old Sony Vaio Laptop VPCSE13FX. As soon as I got it, I put a Crucial m4 256GB SSD in it, loaded a new copy of Win 7 Pro 64 bit and downloaded all of the drivers. The Laptop worked fine for a while, but now, about once every 10-15 times that I boot it up, it is super slow to load, and the keyboard lights go out while it's doing this. Once it finally loads, the keyboard lights come back on. I then turn it off, boot it up again, and it starts up fine.
Don't know if it's an issue with the SSD or not. The SSD has the latest firmware. Oh, I also added a 4 Gig stick of Crucial Ram in it once I got it, making a total of 8 Gigs. Could this be a Ram issue and not an SSD issue? I don't think it's the OS, for it usually works fine with no other problems.
The keyboard lights going out indicates to me that the problem is not RAM or SSD but more likely Motherboard and or some kind of power issue. Get the laptop checked out while it is safely under warranty.
It should not have voided the warranty any more than upgrading the RAM would. Sony would find itself with unhappy customers if customers could not do basic upgrades. If it is a Motherboard problem then putting in a SSD would not have caused that just because a SSD had been put it. Go to Sony. Be firm but polite if there are any problems though I should think they would just sort it out.