A miner is more than just one single chip that either works or does not work. A hardware error is basically just a calculation that went wrong.
E.g. you want to calculate 1 + 2 and you know that the result must be odd so when you get 4 you know an error happend, just not which and where. With simple checks like these computers can check if they are working correct or not.
Your miner does this in a similar fashion. It can check whether its fully working or just 9 out of 10 chips.
It is even possible that the chip itself is not damaged but still gets a calculation wrong from time to time. This can happen due to fluctuations in electricity or temperature.
If you make sure that your chips are reasonably temperated (30°C would be perfect, but 50°C is usually fine) and the power supply has a little extra power (~10%) you should be fine.
Overclocking can also be a cause as well as age. Overclocking and heat speeds the aging of a chip. Overclocking usually comes with a increase in power demand as well, which can be another aging factor. Its basically a time/power tradeoff. Your chips will give you more power but die sooner.
Not exactly 5 year old, but if you have further questions feel free to ask
That's a really good explanation, but I would like to make some corrections.
The temperature of the chips depends on your hardware. HW errors are caused by:
-Insufficient Cooling
-Thermal Throttling
-Insufficient Power
-Problems with PSU
-Overclocking is too high
-Chips/Miner actually damaged
Check all of these, make sure that there are no problems with them, and see again. If you cannot get extra cooling, lower the clock.
Overheating can cause permanent damage to your miner.
