Re: difference % solid polymer cap and aluminum electrolytic cap

Not sure on the price difference, but solid polymers do have their drawbacks.
1st, if they fail it's more likely to be short-circuit, and 2nd they're pretty poor at low frequency.
While a liquid electrolyte cap might be good for 90% of it's current rating at 500Hz, the solid polymer type can only handle 5% of rated current.
At 5KHz they'll handle more like 20% of their rated current. Current ratings are typically given for 100KHz operating frequency.
Having said that, most motherboard uses won't...

Re: MS 6340 - Hissing

Cheers for the heads-up Harvey, I'll give them a look next time I dig it out of the closet. I did notice those 4 are Panasonic HFA's on mine (other people have Tayeh) so it's possible MSI got wise to the problem.

The cap that failed on mine was on the power input side of the VRM, so I'm suspecting the PSU over-rippled it. Hissing sound stopped when the cap was replaced, so hopefully that means the Pannys are OK. No obvious problems in the PSU, but it's cheap and nasty so will swap. System's sat spare at the moment anyway, so not too urgent....

Re: MS 6340 - Hissing

In case this helps anyone, I saw exactly the same problem recently (6340 unstable + hissing until crash).
Problem was a Nichicon 4700uF 6.3V HD series (sleeveless style) near the ATX power connector (C12 and C22 on ver:1 board). Wasn't bulged or askew at all, but was venting from the base. Had to clean electrolyte off the board as it had spread over a wide area
Temporarily replaced with a Nichicon 3300uF 10V PW from the spares bag + the board tests fine now (I'll do it properly one day ).

I'd swear the sound was...