@badactor I have a psu-006 550watt, the case is a bit old but it has enough space for all types of motherboards. My main cause is running some simple games like lol,cs:go, pro,nba 2k, etc while browsing and maybe solidworks (mechanical enginnering software) or photoshop (nothing special). I know that these tasks are quite simple but since it's the first time iI'm building a pc I would like it to last for at least 4 years so I'm aiming for an i5 instead of i3 (upgrades to other parts will come gradually).
@n0ns3ns3 I was thinking something really similar to your suggestion, my only question is about the mobo: Do I need a z170 if I'm not planning to overclock?
Thank you both for your quick answers.