I would give this seller adequate time to either give a refund or make up to you what he has done in some other way as the chips are clearly not excellent if warped and not noted as such. For me, adequate would be two weeks from the time I first contacted him with the problem. If no response, negative feedback is in order. If he has not given you feedback as yet you can pretty much expect negative feedback from him shortly after yours. I would also contact eBay and send them all your correspondence with the seller. It is a shame that we must at times deal with people who think pulling the wool over our eyes is better than being outright honest.