I'd grab one of the cx-3 dual port that go for about 28~35 on ebay. Cross flash it and put it on your windows box. Run opensm on the same windows box and flash it through that.Using monoprice dac's (have a qdr IBM switch which my 2 mel/emc switches are going to replace, and the dac's work fine on it. however, it only does l2 ethernet switching when not doing ib)
Open Subnet manager is running on one of my servers, doesn't come up.
cards i use are are cx-3 bcct's (which don't do InfiniBand)