I just used the Minigun++ with AP rounds while wearing normal T-51b Power Armor. You'll take it out in less than 250 rounds depending on your Guns skill and the condition of the minigun.
I perfer to use the Minigun++ with AP rounds to take all any and all Deathclaws. The LDs will go down when using theMinigun, but it takesa lot of rounds and you need to keep some distance between yourself and the damn Deathclaw or you're DEAD.
I have no idea what my character's total worth is, but now that I'm done with Dead Money I have just over 100,000 caps on my character along with several powerful weapons and power armor.
(BTW, gold bars are awsome, if you can find someone to sell them to.)