PSU upgrade question.

[Robby]

And I doubt that the Athlon X4 will be much faster. Of course it's only faster when an application can handle all 4 cores! But only some modern games are using multiple tasks. Your current CPU should be fast enough for 720p video rendering.

I'm getting the opposite of that. It's fast, but it just can't handle it. It's not the CPU or my RAM at all, or I'd experience different problems too, and stress-testing at 100% with Prime95 yielded absolutely no errors, even if it went on for like 3-5 hours. And it's not the editing software, I've tested the same configs on my neighbour's PC with a quad-core CPU and set his PC to run with 4GB RAM, like me, and it was showing effectively no problems. Main reason for this smaller upgrade, alongside some minor boosts (the CPU sort of bottlenecks my GPU).

450W is enough for such system

Well good enough for me. Just making sure. I can get an upgrade either way (not too expensive, one of them)