Hello all,
 
If i split a single 8-pin pci-e cable from the PSU to a 2x 8-pin can i safely draw 300 watts over that single cable (which is then split into 150w per 8pin connector)? Or when i read that an 8-pin connector is capable of drawing 150 watts is that max per each connection to the PSU? I hope this makes sense and thanks in advance!

Thanks. I guess here is what I am getting at i should have been more direct. Lets say i have a GPU that requires 1 8 pin connector and 1 6-pin connector and pulls 250 watts. Can i use 1 pci-e cable and split it to 2x 8 pins and plug both 1 8 pin and 6 of the other 8 pin into the GPU and remain safe?

smmachnik
Can i use 1 pci-e cable and split it to 2x 8 pins and plug both 1 8 pin and 6 of the other 8 pin into the GPU and remain safe?

Yes, you can safely use a single pci-e cable to power your video card if the cable splits into two 8(6+2)-pins at the end. Just make sure you stay under 288w.

That's what i needed to hear thanks a bunch!

Okay guys here's another question I have. So an 8-pin connector can pull 150 watts. So from the PSU: 8-pin plugged into PSU, other end of cable (8pin) plugged into and 8 pin splitter, which splits off to 2x 8-pin(or 6+2). Here is where my logical side is having difficulties. If an 8 pin connector can only safely draw 150 watts, how is the 8pin at the end of the main cable (opposite of end plugged into the PSU) able to deliver almost DOUBLE that to the splitter cable? In my head this is saying that this is no different than pulling 225 watts right off of a single 8 pin connector from the PSU Since you have 225 watts flowing through that single cable anyway to get to the splitter. Not that i would every do this but where am I off here? Or am I correct and it just depends on what the wiring can handle?

That's my point. where you connect the splitter  -----=====
                                                 in the middle here^
 
Lets say the cable is rated for infinite power draw. The 8 pin would be drawing more than 150 watts which is what the 8 pin connector there can safely pull no? That 8 pin that connects to the splitter is deliver 150 watts to each 8 pin split off from that (if the device its connected to is drawing that much). Sorry electricity isn't my forte. So essentially if you have both ends of the splitter drawing 150 watts or even 100 watts EACH, you are drawing 200-300 watts from that 8pin connector going into the splitter which is only rated at 150 watts. 
 
To try and simplify my explanation: If i have 1 garden hose connector that will burst  at a rate over 10 gallons per minute and i hook up 2 garden hoses to that single one and they both pull 10 gallons per minute it would be overworking the first hose connector. I am trying to comprehend why the first hose connector can run 10 gallons per minute max but if you hook up 2 hoses to it even at a total of 15 gallons per minute its fine. Or am i correct to assume that the main hose connector could burst at any time (8 pin feeding the splitter melting). I wondering how i see EVERYWHERE that a 1080 or ti or whatever card it may be takes 1 8pin connector plus a 6 pin and people are just splitting 1 connector into 2 pulling 200+ watts total from a single 8 pin source rated for 150 watts. That is the bottom line to my question.
 
Edit: Or am i over thinking this and i can disregard any connectors connecting wires as it essentially just makes it a "single wire"? Therefore the 2 ends of the splitter I could act like are the "only" connectors and it doesn't matter what they draw as long as the wiring is capable.

@QuintLeo Thanks. So I am now at the conclusion it is safe to say that if i wanted to power a 1070 (single 8- pin) at a draw of 150 watts and a powered riser board (6-pin) i could do so with ONE pcie cable from PSU to a splitter cable which provides 1x 8pin and 1x 6+2 pin. I don't know why i got so hung up on that first cable connector going into the splitter's connector. Thanks everyone for the help.

kvncrldlcrz
im currently using a BP 610 EVGA psu
which only have a single strand of pcie connection
(2x 8 pin (6+2) daisy chained)
to power my RX 5600xt (150 watts)
that requires 2x 8 pin.
So my question is,
Can i still add another RX 5600xt(150 watts) by using a 2pcs of 8 pin "Y" splitter (so total of 4x PCIE 8 pin (6+2))? my psu have a 50amp for the +12v. thank you in advance.

Short answer... No.
 
You're really playing with fire if you were to do this. You CAN do it; but your power supply is going to have a tough time delivering enough power under load to the cards. You'll see system instability and crashing all the way to melting cables if the power draw is too demanding on the cables/PSU.

I would recommend getting a new power supply with enough dedicated cables to deliver power smoothly.