Uncasing a PSU

discopig · Post by **discopig** » Sat Aug 01, 2009 11:59 am

Hello all,

I am looking to do an ITX build and will be using (perhaps) the PSU that comes with the IN WIN cases. http://www.in-win.com.tw/products_pccas ... id=49#here . I am wondering is it safe to remove the case of a psu and mount it inside a case without and shielding? I am wondering because it doesnt make sense to use a loud 40mm fan to blow air through it when I can remove the case and the fan and (with proper case airflow) have cooler and quieter air blowing over the PSU heatsinks.

Any one actually tried something like this?

Another thought, any PSUs (better quality ones) that are amenable to dismantling and "reconfiguring" the boards to alter the form factor?

I want a frankenpsu!

Thanks in advance for your help,

Adam

swivelguy2 · Post by **swivelguy2** » Sat Aug 01, 2009 12:55 pm

It's safe as long as nothing is going to make contact with any of the PSU elements.

Bluefront did a mod once where he replaced a PSU cover (on a different sub-ATX psu) with a custom, perforated one to allow it to run without its own fan. Here it is:

viewtopic.php?t=45258

Also, have you thought about a picoPSU?

jessekopelman · Post by **jessekopelman** » Sat Aug 01, 2009 3:53 pm

You need to be very careful if you do something like this. A lot of parts of the PSU, including heatsinks are live. This means no more opening your case without unplugging PC and making sure you've discharged PSU capacitors, let alone messing around with stuff without turning off the PC. Touching a live PSU innard can injure you fairly badly.

I recommend doing something more like what swivelguy2 mentioned -- replacing the PSU cover with something more to your liking, rather than leaving it bare.

larrymoencurly · Post by **larrymoencurly** » Wed Aug 05, 2009 7:09 pm

Don't attach anything to the heatsink with the high voltage transistors attached to it because:

1. If the thin insulation on any of those transistor fails, the heatsink will have high voltage riding on it.

2. Some PSUs are designed so that heatsink is connected to high voltage, and I believe it's for shielding against RF emissions. The heatsink isn't grounded because that could make it hazardous if the wall outlet was ungrounded and the transistor insulation failed. IOW the high voltage connection is for safety, but it provides safety only if the PSU is inside its metal box.

Didn't Mike publish an article several years ago, showing that PSUs ran hotter without their metal boxes because the box directed the air flow over the heatsinks?