Can I restore my PS3 Game Data via the PS3 server?

I know it's an odd question...

Basically, I have to get a knew PS3. If I can log back in to my account and open a new game file, shouldn't I be able to retrieve my achievements from PSN?

Like, I have Warhawk...If I log back into PSN and create a new game file, won't PSN know that it's me and bump me back up to my level and show how many points/kills/etc.. I have?

Same thing with MAG...if I start a new game but log in to my PSN account, shouldn't I be recognized with the level I was at before my old PS3 shut down, with all my achievements?

I just don't want to lose all of my data, considering it took me a while to get there.