Hi! Thanks for the advice
1) Which motherboard will you recommend me for my needs?
2) Which colour of WD will you recommend? I might need 2TB is due to lot of movies storage.
Is there any other good GPU to recommend for my needs?
Mobo wise what Mr Alternative said is very true. As for your hard disk question, personally I do not like the WD blue and green versions due to the durability issues I had with these drives previously. While I agree that while 7200rpm hds have a better access time as compared to a 5400rpm hd statistically, do note that you are mainly using the hd for STORAGE. I do advise you to get a usb3.0 xfer rate hd where you can go for higher capacity hd at a lower cost/internal hd of other brands (be it running at 5400rpm/7200rpm). In the past, there was a hype with the 7200rpm and 10000rpm hds due to the fact that people were using them as os drives as ssds were very expensive back then. They have significant improvement which can be seen visibly as frequent read-writes are common on an os drive.
On the other hand, for storage wise, the minute visible improvement might not be a deal breaker so much so to make a 5400rpm hd obsolete. That is why you still see a mass production of these drives even till today. *But more importantly, you are not constantly installing programmes and running them on storage drives.* Of course if your budget allows, you can always go for higher rpm drives though the small performance improvement is always subjective to individuals in the viewpoints of storage purposes, and whether or not can your eyes really pick up the difference between milliseconds and a few seconds of your time.
*On a side note, install your os, games and other programmes on your mx ssd and after which, move those installers' exe files to your hd. Do not install games on a hd if you have a ssd lol.
