I bought 2 x 8 gb ram chips yesterday in Bolton at £22 each. I sold 2 x 4 x 4gb ram chips for £2 each. The 2 x 8 ram chips would not work in my laptop. The assistant assured me that they would. The laptop screen went blue and a windows repair did not work. Today I took the 8 ram chips back and got a full refund. The shop would not swap the items as I hopped. I had to buy the 2 x 4gb chips at £7 each which I think is a joke.