Make sure if you add any hardware item at a later stage, that it is compatible. As most computer issues arise just after installing a piece of new/used hardware.
Also make sure that you get the pc fixed at the place where you bought it from or directly by the manufacturers. If you or a third party tries to fix it you may void the warranty.

We had a computer built for personal use and less than a year we had to have the motherboard replaced. The company was still in business but has since closed shop. Last month we had the same problem but were told that if we wanted to claim the warrenty we would have to contact the company that we purchased the computer from. The computer is still under a year old. What can we do as we've had to pay to have it repaired this time around. Also on having the computer returned to us we had to return the computer to the shop because the fan was louder than usual. Apparently the gaming cards fan bearings were worn. We had to replace this with a cheaper card due to the cost involved in replacing it with a similar card. We should be able to claim warranty on this shouldn't we. Is it a case that the repair company just couldn't be bothered? They were aware of our situation before we took the computer in.