sorry for the last part i forget to respond to it
thank again for your response
my part :
asus strix x99 mobo power whit 8 and 4 pin from the corsair
2 x r9 290 watercooled porweder by 2x8 and 2x6 pin total 4 cable from the corsair
4tb HDD powered bysata by the corsair psu
12 fan connected 4 fan by molex (pwm signal to the mobo)
2 swiftec mcp 35 powered by only one molex on 300w (maybe less) noname psu
İ also try just the original cable that come out fron the box
i use extention sleeved cable connected to the orijinal corsair cable
if i connect event only one pump on the psu its shutt down
My gpu are powered by a total of 4 pci 8 pin and 6 pin pci each not a single 8+6 but 2 straight of the psu for each gpu
i have try whit and whitout the sleved cable extention
i have try whitout any fan and HDD
how a noname 20 year old psu that give a max of 300w can run my 2 pump my HDD and 12 fan and my 1200hx corsair not
i hope i didnt forget anythin