cyrnel

If the ratings are correct the PSU _should_ be adequate. Real 400W supplies go a long way used correctly. That thing has modular cables and two rails. Make sure you're balancing output between the two 12V rails and not lumping everything onto one.

Try disconnecting power from the optical and maybe the extra HD and see if it lasts longer.

Edit: And of course make sure the fan is working. I see plenty of DOA temp-controlled fans take out power supplies.

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There are a vast number of people who are uninformed and heavily propagandized, but fundamentally decent. The propaganda that inundates them is effective when unchallenged, but much of it goes only skin deep. If they can be brought to raise questions and apply their decent instincts and basic intelligence, many people quickly escape the confines of the doctrinal system and are willing to do something to help others who are really suffering and oppressed." -Manufacturing Consent: Noam Chomsky and the Media, p. 195