Poor products

I bought a GPU from Rectron Durban in 2017, it was a Gigabyte Geforce 1070 8GB card, 2 years in 2019 later it had blown completely. I took it in as it was still under warranty and they replaced it with a Gigabyte Geforce 1070 8GB Windforce OC edition which as of last week has basically stopped working. In 4 years 2 GPUs have stopped working where ONE card has an average life span of 5 years minimum. Now that the warranty on the original purchase has expired apparently there's nothing I can do about it because there's no extended warranty when it was replaced. This is completely unacceptable to have 2 stop working in such a short time. I have not over used them when it comes to graphics in games either, I do not play any high intensive graphic games and any game I do play I do not play on ultra settings. Nowhere did they give any terms & conditions regarding warranty and I was also not informed that the replaced card would not have a new/extended warranty on it.