As I've mentioned elsewhere - my BFL started to play up until one FPGA seemed to be dead
(though I hacked cgminer a bit so it was happy hashing anyway at half the rate and ignore any errors or problems)
Then it died
Then it worked again, and died again etc etc
(the fix each time was usually a power cycle)
In the end I simply reflashed it with the 880 bitstream to see if that would kill it ...
BFL0 Temp:57.80°C MHS av:873.39 Accept:5,790 Reject:25 HW:0 U:12.06/m
Yeah these things are just stupid
Of course that is really good for me - but why the hell is it actually working?
No HW: no errors no problems but it's running at 57°C (it varies from about 55 even up to 58 sometimes)
I've been running it with the 880 bitstream since 26-July - only twice did it play up ... coz one of my kids moved a bean bag behind were it sits at my feet on the floor and thus the air wasn't getting away well so it started to throttle badly (happened twice)
So I'd say (what I said back when I got it) the throttling hardware in these things is just ... not very good.
I think that BFL agree also ... since they didn't put it in the MiniRig cards.
Edit: mine is the one with the new heat-sink but only a single fan on top