Triple core processors

It used to be the case that triple core CPU's were sold like that due to 4th core not working (properly/at all) - is this still the case or are triple core processors being made with three cores at the very start ?

If triple core CPU's are still being produced with a faulty 4th one, does that increase the rate of total failure for the complete CPU or is there no statistical difference between failure rate and 4 core processors ?

All triple core processors are quads with one core shut off. The core isn't necessarily faulty, it may work perfectly and have just been disabled because the manufacturer has more orders for tri-core chips than it has quads with a failed core.

There's no increase in failure rate with triple cores. A flaw in the chip that knocks out one core won't have any affect on the other three.

I suppose in theory, with one core disabled the voltage draw is reduced, so the heat is reduced, which should mean a more reliable, longer lasting CPU. Assuming a quad-rated cooler is used, that is.

Thanks for that!

In reply to a post by DrBC:

All triple core processors are quads with one core shut off. The core isn't necessarily faulty, it may work perfectly and have just been disabled because the manufacturer has more orders for tri-core chips than it has quads with a failed core.

There's no increase in failure rate with triple cores. A flaw in the chip that knocks out one core won't have any affect on the other three.

even if it is classed as faulty, most of the time it is just because the core don't meet a certain standard. i built a computer last year with a phenom dual core, got the board to activate the other two cores and it is still working fine. so he got a quad core for the price of a dual core.

You are right. I built my pc three years ago and whilst researching for which CPU, motherboard etc. to get, I read somewhere that most processors are manufactured to be quad core. If one or two cores are faulty etc. then they are shut down and the processors are then sold as two or three or even single core processors!