My HX620 is dead (I think)....

[Defenestration]

After building my new PC, I thought I'd try a bit of overclocking. Everything seemed OK until I dropped the CPU's multiplier from 9x to 8x and upped the FSB to about 420, when it booted into Windows OK but then shut-down after a few seconds of running Orthos.

At first I thought the problem was with the CPU or mobo, but I tested with a new CPU and the problem still existed. It's possible the problem is with the mobo, but when I tested the PSU outputs with a multi-meter I only got a 2.97V output, with all the others being 0V.

I remember hearing what might have been a pop when the system shut-down, which might be a fuse blowing (if indeed the HX 620 has fuses ?). I am now RMA'ing for a replacement.

My question is - what could cause the PSU to blow a fuse and fail given that upping the FSB to 420 should not have caused the HX 620 any problems ?

Because I'm not sure exactly what caused the problem, I am also RMA'ing the mobo in case there is some problem with that.

[Blitzen]

I somehow seriously doubt that pop was your PSU.......
More likely something on the mobo imho.....

The actual power its trying to dish out wouldnt change hardly at all so an overclock certainly wont kill a PSU...not even an 'El Cheapo' one, let alone a Corsair.

[Defenestration]

That's what I was thinking, but checking with a multi-meter gives my previously reported results. I understand the load can affect the readings, and a MM doesn't provide load, but should I be getting those readings from the PSU ?

I'm still interested as to whether the Corsair uses fuses though as, while it is a good PSU according to all the tests done by various review sites, a top notch PSU would simply reduce the output when overloaded, rather than rely on a fuse (this obviously costs more to implement than a fuse). The only limiting factor then would be heat caused by the overload.

Unfortunately, I don't have any spare parts (or PC) I can use for testing - I ended up buying a new E6300 from PCWorld specifically to test if my CPU was buggered (only to take it back a few hours later for a refund when it proved my CPU was not at fault ).

[amjedm]

Why don't you post in the Hexus Help section to ask if anyone lives near you so you can try out the psu in their system?

[IAmATeaf]

A PSU would normally have a fuse on the 240 input, if that blew the PSU wouldn't even come on. Also modern PSUs won't even normally start up if they detect no load, not sure why this is but may be related to PFC which attempts to balance the load between the various rails.