Overheating Problem

[Limber]

Hi everyone, I've got a nasty overheating problem with my computer, and need a bit of advice. I'm looking for a way to increase the exhaust airflow of a Seasonic X-650. I've explained my situation in more detail below for those interested, but you can skip to the end if you want to get to my questions.

I have an Antec Solo case with a mid-range GPU and a full compliment of hard drives. I recently donated my former power supply to my parents' new computer, and purchased the Seasonic X-650 while it was on sale as replacement. I failed to consider the thermal consequences.

Unlike my previous power supply whose fan was always spinning, the Seasonic's fan never kicks in since my computer isn't very power-hungry. The case's rear exhaust fan is actually pulling warm air down from the X-650 into the case, exhausting it, and pulling it back in through the power supply again in a pointless closed loop (tissue paper "sticks" to the grill of the power supply). There is virtually no fresh air flowing into the front of the case anymore. Out of curiousity, I briefly duct-taped the X-650's fan grill to see what would happen, and fresh air started flowing into the front again.

Anyway, with the case buttoned up, all of the major components (CPU, GPU, hard drives) are 10-20°C hotter than they used to be, with the hard drives suffering the most. I blew it. For the moment, I'm forced to run the computer with the side panel removed to protect the equipment inside.

Questions:

a) I'm thinking about plugging in the power supply's fan externally, either to a motherboard header or a molex connector (possibly replacing the fan if necessary). If I do, will the power supply still function properly, even though a fan is no longer plugged into its circuit board? (I realize I'd be voiding the warranty, and I'd probably have to do a bit of damage to the power supply's casing to re-route cables.)

b) This is a long-shot, but it can't hurt to ask... can the existing fan's behaviour be modified so that it's always running?

I've also been looking at new cases (Fractal Design's R2 looks nice), but money's tight right now, so modifying the X-650's fan appears to be the most economical approach for now.