Hi bon
I'm affraid I won't help much, but I'd been using Blizzard IV 30/50 for several years, without any cooler, with standard PSU and inside desktop. Didn't have any problems with it, didn't notice any heating. I used it with 4MB at the beginning and then with 32MB EDO and 68882/50.
Freezing can be caused by +5V falling too low. If you didn't use your expansion slot till now mayby try to clean it a bit. For so many years it could have got dusty.
Good luck
PiR
P.S.: Once I owned a accelerator that didn't like my HD. With HD from another producer it worked correctly.
