You can put a 120GB HDD in your PS3!

[Dave]

Playstation 3 HDD Replacement Mini-Guide

We here at GR, never content to leave well enough alone, have replaced our puny Playstation 3 HDD with a monster 120 GB HDD. We also wrote this mini-guide on just how to do it for those of you who may be a tad afraid to try it.

You will need:

1 NOTEBOOK 2.5MM HDD SATA ANY SIZE (We recommend staying with the same RPM as the PS3’s original HDD, 5400RPM. You can upgrade to 7200RPM, of course, but we cannot promise that it will not have ill-effects on your machine.)
1 MINI PHILLIPS HEAD SCREWDRIVER
1 MINI FLATHEAD SCREWDRIVER
1 SOLID PLACE TO WORK
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To answer your question before you ask, the only thing that gets erased is game saves. Your network ID info, your console settings, and even the 1.10 update all remain in place when you do this HDD swap. Neat eh?

There you have it folks, easy as pie. Of course, if you choose to perform this modification, GamersReports accepts no responsibility if you break or otherwise harm your console. As always, if you are not sure you can perform the mod without damaging your hardware, do not do it at all.

http://www.gamersreports.com/article/43/