Used AMD Cards

We've all heard about the dangers of buying used AMD cards, that were once used in the infamous "Mining Rigs" of lore. I'd like to ask what kind of negative side effects can you expect from a card that was used extensively for mining? Which card models are more likely to have been used for mining? Does anyone have personal experience with a used card that they found out the hard way had been "Burnt out" by bitcoin mining? What percentage of used AMD cards for sale might have been used in mining?

I have an R9 270x I bought for $120. Works great, easy to overclock, plenty of headroom, apparently was not used in any mining, just light gaming for a few months.  If I buy a used R9 280 or 280x, what danger of buying a mining card is there? 

I have a Powercolor R9 280X that was bought cheap when a miner broke up and sold his stuff. Absolutely no problems with it at all. I also have a secondhand MSI GTX 770 Lightning, again no problems with it - obviously it didn't belong to a miner.

I think the key is to make sure you get a bargain and you know that that the card has not been overclocked or been tampered with, also pick brands with good coolers that have little negative feedback. If you search on ebay you may also find some second hand cards being sold with a limited warranty from the seller.

There are definitely AMD cards out there that are completely functional. Most sellers are honest and will tell you up front if it works or not. Heck few days ago I sold an HD 7950 (aka r9 280) for $115.00. The buyer is very satisfied with his purchase too. 

Thing is, decent NEW cards are ridiculously cheap these days.

I dont think its worth it, save up a little and buy it new.

Warranties are useful things to have (not that I have ever needed them as I have been lucky, all my amd stuff has been golden... although I think i may have just jinxed myself there now :P ).