I am building a new pc and is planning to use this motherboard MSI B450M PRO-VDH. It has two system fan headers but i wanted to install more so i was wondering if i can use fan splitters on both headers ? would it be safe?
Yes, you can use splitters on both headers. The key is not to pull too much current (amps) from a single header. Most headers allow for a max of 1 Amp (check your owners manual ... if it says). Most fans draw in the 0.1 Amp - 0.2 Amp range (look at the sticker on the fan hub). Keep the sum of all your fans on that splitter below 0.8 (80% of 1 Amp) and you will be fine.