this 100% depends on the cards.
If these are RX 470/480/570/580 then that's WAY too much draw for a single strand of molex (which has only a single +12v wire)
For safety, I generally use a single strand of Molex per GPU.
Only use two VGA connections per strand max, no matter the cable type and preferably only one. With three you are running close to overloading the cable and with four you WILL burn up the cable, the PSU or both. If you don't have enough cables to use two per strand at most, you need to get a bigger PSU that has more connections.
They are 470s and 570s.
The VGA are all plugged in directly, but I'm talking about the riser power. I have a Perif to 4-molex string. Trying to avoid using 4pin molex to sata string to sata-psu.
Unless you did mean VGA to Molex for the risers?