Did some checking online and walang diagnostic LEDs yung board mo. But it does produce beep codes if you attach a pc speaker to the speaker header on your motherboard. Although not everyone will have a mini-speaker like this.
Minsan nag boo-boot-up then after 2 mins wala lahat ulit lahat pero power on parin.
For clarity, when you say nag boot up, do you mean may nag appear sa screen? If so, could be a cooling problem due to dried up na thermal paste of a failing cpu fan.
Otherwise, best bet is to strip down to bare components and swap parts to identify which one has the problem, if you have spare "known good" parts. Don't disregard trying a different working PSU if you have one.