Bought a CyberPowerPC gaming system. The two front RBG fans were a little loud; BIOS settings only seem to control CPU fan and two top fans. Installed two Noctua PWM 4 pin fans; LEFT 2 pin RGB cables unconnected. Fans didn’t spin up; resetting BIOS didn’t help. Their tech support didn’t respond.

Thought maybe reversed pins and did harm (cable from case has no clip; have to tape together). So bought KazeFlex fans, made sure pin 1 matched…still nothing. All new fans not RGB.

Cable from case comes from splitter connected to MANUAL switch connected to something else to power supply. Third cable from splitter goes to mboard. TRIED disconnecting third cable…nothing.
Please help. CyberPowerPC said it’s third party and bailed.

Case: Cooler Master MasterBox MB500
Mboard: ASUS Prime Z490-V
PS: Thermaltake Toughpower PF1
Eliminate the splitter and TEST 1 at a time...took a picture: https://imgur.com/txO9KoX
not just a splitter...two with green tape top left go to fans
three way splitter has coolermaster label
it goes to large box with button which goes eventually to psLooks back yard HACK to me...just sayin.