Question How to powerup my new motherboard with my old PSU

[Shlomi1515]

I Have purchased new motherboard https://www.gigabyte.com/il/Motherboard/Z390-AORUS-PRO-rev-10#kf
it has 8 pins + 4 pins additional power to the CPU my old PSU is bulit with only 8 pins

my old PSU is TX850M https://www.corsair.com/us/en/Categ...es-2017-config/p/CP-9020130-NA#tab-tech-specs

I Didnt used any of the modular slots its empty can I buy a cable and connect it from there? for additional power?
if yes can you reffer my to a link where to buy? and where exactly to connect i dont want to burn my new motherboard

 

[Phaaze88]

The motherboard will still work without the 4-pin connection.
EXCEPT:
-You won't be able to overclock
-Not 100% sure about this one(if someone can correct me on this), but I think the 9900k will crash when doing it's normal boost clocks. Reason: the 8-pin is rated for 150w of power, and the 9900k can easily exceed this limit.

The only real solution to this is a new psu with the proper connections. Do not take shortcuts(adapter) with the most important part of your PC, or it can end up costing you more than the price of a new psu.

 

[Shlomi1515]

my psu has connection that i didnt use see picture
i think i cann connect the botton left socket to my CPU right?
to connect only 4 pin and leave 4 pin unconnected

does any1 have that? 8pin + 4 pins connectedand and extra 4 pins not connected?

 

[Phaaze88]

Hold up-
I had to look around, because I had trouble finding good pics of the cables, but your current psu isn't compatible with that motherboard.
It's the 4+4-pin cpu power connector. The 'key' doesn't match the 8-pin socket on the motherboard. *Power supply connectors are keyed

A pic of the cpu power 'key': https://www.jonnyguru.com/blog/2017/06/05/corsair-tx850m-2017-850w-power-supply/ (in the 3rd pic from the top)
Motherboard: https://www.newegg.com/p/N82E16813145098 (hover the mouse over the cpu power sockets)

You need a new psu. There's no shortcut for this.

 

[Shlomi1515]

What do you mean keyed it just power
I have connected the extra cable as follows

8 pin + extra cpu cable i recieved in psu box

 

[Shlomi1515]

Update: I have connected it to the power 8+ 4 pins + 4pins hanging around not connected and it works great no smoke i dont need to buy a new PSU saved 150USD

 

[Phaaze88]

You were able to figure it out...
I managed to confuse myself looking back and forth between the images. Sorry.

 

[geofelt]

Update: I have connected it to the power 8+ 4 pins + 4pins hanging around not connected and it works great no smoke i dont need to buy a new PSU saved 150USD

You did it properly.
There is a hard wired 8 pin eps connector and what you used is a secondary 12v eps cpu connector.
Leaving the +4 pin dangling is what that setup is designed to do.
The +4 is there in case you had a motherboard with two 8 pin requirements.