Question MSI B450 Tomahawk issue Please Help

Mar 2, 2019
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Just bought a MSI B450 Tomahawk motherboard and I have a Lian-Li case that has a three pronged Power LED. The motherboard however only has 2 prongs. It does not look like it is able to be split since the middle prong of the three looks empty.. I am really at a loss since I do not see anywhere on the motherboard a seperate 3 Prong location.

Currently the computer will not turn on at all with all new peripherals.

I just bought all of the following..

MSI B450 Tomahawk motherboard
Radeon RX580 Graphics Card
Ryzen 5 2600 X
EVGA 500 W power supply
2x8GB Gskill DDR4 2400

This I sure hope I dont need to buy a whole new case.... cause I love this Lian-Li..

Please Help!
 
Mar 2, 2019
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Update.. I was able to swap the pin with a needle.. plugged everything in the way the diagram says, and still no power.. Is the power-supply not enough power with the other peripherals? Im extremely confused..
 
Update.. I was able to swap the pin with a needle.. plugged everything in the way the diagram says, and still no power.. Is the power-supply not enough power with the other peripherals? Im extremely confused..

The power contacts on motherboards come both ways: some with the two pins next to each other (as on the Tomahawk) and some with a gap between the two pins (which the Lian Li anticipates). Usually the case power connection is made up of two single pin connectors to accommodate that. It's unfortunate Lian Li doesn't.

Can you test that the system will turn on by simply putting a short across the two "POWER" pins on the motherboard. I'd use a screwdriver to make the short. It only needs a momentary contact to work, once the system powers up you can remove the screwdriver and proceed.

If it does turn on then you'll know that the switch in the case isn't working the way you expect. I'd try reversing the pins in case it's polarized with a diode.
 
Mar 2, 2019
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it does not seem that the short worked.. My guess is hopefully it is just the powersupply and the lack of "power" since its 500W. If thats not the case.. Im totally lost...
 
it does not seem that the short worked.. My guess is hopefully it is just the powersupply and the lack of "power" since its 500W. If thats not the case.. Im totally lost...

If you doubt your PSU you could do what's called the 'paperclip test' described here:

http://support.antec.com/support/so...19-is-my-power-supply-dead-the-paperclip-test

You have to disconnect all PSU connections to system components before making the test but it will tell you if your PSU turns on. A 500W rating isn't too bad...and even if it should prove inadequate in use the initial power-on isn't a heavy enough load to stress it out, assuming it's fault-free. Hopefully the paperclip test will help you figure that out.
 
Mar 2, 2019
4
0
10
If you doubt your PSU you could do what's called the 'paperclip test' described here:

http://support.antec.com/support/so...19-is-my-power-supply-dead-the-paperclip-test

You have to disconnect all PSU connections to system components before making the test but it will tell you if your PSU turns on. A 500W rating isn't too bad...and even if it should prove inadequate in use the initial power-on isn't a heavy enough load to stress it out, assuming it's fault-free. Hopefully the paperclip test will help you figure that out.
So I did the paper clip test and the single fan in front of the case did power up..

I then tried the screw driver test to the pwoer +/- and nothing happens with that..
 
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I'm a bit at a loss...by now I'd have checked the switch wires from the front panel with a multimeter and to see if it's working as expected. Check with leads both ways to see if it's polarized...but you do need a multimeter to do this.

Also try resetting CMOS on the Tomahawk: remove the CMOS battery and short the CMOS reset pins (check your manual on where they are), leave the battery out a few minutes before putting it back in and reconnecting to power mains.

Double check ALL connections to the motherboard, making sure everything is well seated with no loose connectors. Then try to turn on with the front panel switch connected again. If it still doesn't work or at least attempt at powering up (flashing LED's) then maybe something is amiss with the mobo.