It sounds like you have moved along but no luck yet. Your trouble is not Windows 10. Not the hard drive as you stated you tried different drives. I do not like the sound of sparking as you plug in the power supply, it should not be drawing enough current to spark as you plug it in.
So lets start over, remove all cards plugged in to the motherboard and remove it. Look to see if any of your stand off the board would screw into are out of place touching the back of the board, Check and then check again. If this is ok, remove the processor and make sure it is seated correctly with no bent or missing pins, carefully put the cpu back in and scrape all the old thermal compound off if it had a pad type and use a thin smear of thermal compound between the cpu and cooling rad. Check the rad to be as flat as possible no lumps or bumps. Note only a thin swipe of compound is needed, not thick just a smear over the total cpu. Too much compound can actually hinder heat from being taken away. The fan speed sensor for temperature of the cpu is under the cpu in the area center of the pins. When I attach the cooler and fan I sort of wiggle it to positive have the compound thin out evenly.
Ok now put in only two of the original ram in slot one and three same color. Some power supplies have a temperature sensor that goes on the motherboard, this goes just up and to the right of the 24 pin power plug.
Your case will have a plug from the front panel to the board bottom right. The extra 4 pin from the power supply goes in the 4 pin plug up and to the left of the cpu. The cooling fan from the cpu ONLY goes up and to the right of the cpu The case fan only goes up and left of the top pci express connector. Use only one hard drive and serial port one and a black power connector. Use only the board video and keyboard plus mouse connector or the rear panel usb connectors, do not worry now about the other plugs . No optical drive only one hard drive, the 24 pin power plug, cpu fan, case fan, front panel start button in the cable. the 4 pin cpu power plug.
I have had a mounting stand off rubbing on the back of a motherboard causing havoc, I have had over thermal compound applied causing fan speed trouble. I have had a bad power supply spark when it is plugged in . Do not attempt to use a 20 pin power supply on a 24 pin board, some boards will work but you are trouble shooting the unit and no messing with plug. You are now trying two memory sticks, the onboard video, one hard drive, re done cooler, re seat cpu. Give this a try and I sure would like you to get or borrow a 24 pin power supply you know is good. It would not have to look like your power supply and can sit outside the case for test with the old power supply totally disconnected. It all sounds like the power supply, but then this new to you board may also be trouble. Let us know.