Dell 630i motherboard failure

Hi I purchased a Dell XPS 630i around October of last year and for the price I paid I feel completely cheated and plagued with many issues. My motherboard has failed for the second time today since i bought it. A representative is coming by tomorrow i suppose to verify this issue.Because this is the second time this will need to be done and I have a strong feeling know it won't be the last I do not want this have to defective line returned to me. Now that I have investigated this model more in-depth I know I am far from alone,many people suffer the same as I do with driver problems,crossfire never working right, constant crashing,  fan speed issues, and in my case motherboard failures. I am not satisfied with my product at all and want to talk to someone who can assist me in replacing my machine for a different model of whatever is deemed fair. I need a computer very badly for work and this is placing me in a bad situation and the reliability of the 630i was already giving me grief; as a matter of fact I'm writing this message on my Iphone as that was the only computer I have in the household at the time. I do not want a new motherboard I want this thing to be replaced for whatever is similar to it in your current line up of systems as this ill-supported modeled has vanished from your online store, and most of the drivers and utilities remain outdated and unsupported.

I'm sorry if my tone sounds hard or rude but I have been getting more and more disappointed with this purchase at the price i paid as time goes on. Add in the fact that the machine is faulty and this is completely unacceptable. I would really appreciated speaking to a Dell sales associate or manager to see if anything can be done or if I'l just have to wait for my motherboard to blow out again except this time without a warranty :(