psu and mobo connectors

JoeTheProgrammer · May 29, 2015

I have some old PC and PSU is connected to motherboard using 20+4 pin connector like this:

And another 4 pins near CPU like this:

I am having some problems booting up the system (explained below) and I am going to buy new PSU. In the mean time I want to test one of my old PSU (which I used only for about a week despite that it's quite ancient (about 8 years old)). It does not have SATA connectors and only have one 20 pin and one 4 pin connector. Can I connect this old PSU to this slightly newer but still old motherboard? If so where should I put these connectors? Should I put this 4 pin next to CPU and this 20 pin to that 24 pin slot? Would it affect anything? Performance maybe?

I am having a bit of a trouble with quite old PC and it's current PSU. If I disconnect the computer from electricity and then later reconnect it does not want to start up. I press the power button and nothing happens, no fans start spinning... literally nothing as if it was still disconnected. Just lights on keyboard signalizing caps lock and other functions are blinking. This is not related to pressing power button it starts when I connect it to electricity. I've been able to start it up after few minutes when I switch the rear PSU switch few times in combination of pressing PC power button. After this I am experiencing no problems shutting down and booting up that system.

It's quite old PC containing intel quad core 2.33Ghz per core, 4gb of ddr2 ram and stuff like that. Despite it's old it will be more than enough for my grandma so I don't want to somehow destroy it while trying that old PSU in it.