Alienware Aurora R15 may use up to 64 GB of DDR5-5600 or DDR5-5200 or DDR5-4800 RAM. Note that the DDR5-5600 may downclock (run more slowly) to the maximum frequency supported by your system. Here is Crucial RAM that is guaranteed compatible with your system. As for replacing a motherboard, Dell should have parts for about four years after the model is introduced, in order to cover extended warranties. After that, if Dell doesn't have a part you need, the first and most reliable place to try is Parts-People which sells genuine Dell parts  Parts-People also offers a repair services. If you cannot find a part at Dell or Parts-People, you can search for the part number at Amazon, AliExpress, etc. Yes, as you observed it is mostly people with computer problems who write here. The millions of purchasers of problem-free systems don't come here, so our view on product quality and reliability can be unfairly skewed by reading these forums. Whenever touching components or working inside a computer, wear a grounded wrist strap, also called anti-static wrist strap, ESD wrist strap, or ground bracelet. It's a cheap and sensible precaution. Rest the laptop on an anti-static mat or at least a reasonable alternative such as corrugated cardboard. (Repeatedly touching a metal case part is not sufficient mitigation with modern components.)  
Hello everyone, I write from Italy and I use Google Translate (sorry for the mistakes...).I would like to buy an Alienware R15, but I have some doubts for you surely trivial experts:- if I want to replace the RAM to increase it which model can I buy to avoid incompatibility?- if the motherboard (which is owned by Dell) breaks out of warranty, after a few years is it possible for Dell to repair it, replace it, or should the whole PC be changed because maybe after 3/4 years it no longer produces it? Also because I won't be able to replace it myself because it is owned and I will never find it privately or second hand...- I have read several problems among users, it is obvious that being electronic machines they can occur for various reasons. But in the end, are they machines worth investing in? Or are they not that reliable? It is obvious that only those who have problems write in the forums, and those who have everything that works will not write in the forum. So I wanted to understand what the situation is like...Thank you very much for the support.Greetings from Rome  
Aurora R15, preliminary information, I ask the experts for help