Problem with power plug conection

[jazzband4ever]

i have my case, psu, and mobo, but the main power cord from the psu to the mobo is a 20 pin connector and the mobo has a 24 pin input. you know it fits in the first 20 holes but i dont know if i powered it up if that would work or not, i dont think it would. i just wanted to know if there is an adaptor i can buy, if it will work with the last 4 pins open, or if i just have to buy a different psu. thank you for your help.

 

[Cromewell]

you can buy adapters for them, I am using one right now. P4 based boards with 24-pin power will work with a 20-pin