I purchased a Sonnet Thunderbolt Express II to use with my RayDat card, and the fan in the power supply is really noisy.  In fact, they have discontinued the unit for that reason.  I spoke with a tech from Sonnet, and he suggested that, because the RME cards do not generate a lot of heat, I may be able to get away with disconnecting the fan from the header.  He did say that that solution is not without some risk.  If it wasn't for the fact that their new chassis is almost $1,000, I'd just take the loss and get the new unit.

Is disconnecting the fan a viable solution?  Does anyone have any experience with this?