Unlimited Power Node Glitch | Dead Space 2
TIP: This is where you can earn unlimited number of Power Nodes and ruby semi-conductors. Save your game, exit it and reload it. Now, make your way back to the secured storage room earlier and you'll find replenished power nodes. (If you see credits only, just restart the checkpoint and try again.) Now head back to save your game, reload the saved file and do it again. Sometimes you'll get one or two power nodes. If you're lucky, you'll find two nodes and Ruby Semi-conductor.
This video is from our unofficial game guide. You can view the full guide here