I cant remember what plug in s go where,, after Itook my Compaq Presario S4020WM PC its the coords on the inside the plugins that say CPU or master sslave

SOURCE: compaq presario s4020wm

you mean the internal power supply? that's available for around 20 bucks anywhere online..usually called a PCXT power supply..big issue is finding one that's identical with connectors..

take yours out, and then maybe there will be a part number or maker on the label.

SOURCE: Opening a Compaq Presario S4020WM side panel

Check here : http://h10025.www1.hp.com/ewfrf/wc/documentSubCategory?rule=39140&lc=en&dlc=en&cc=au〈=en&os=228&product=326832
Click on HP Home on taskbar to find full menu of services.
Cheers.

SOURCE: Pc keeps shutting down when trying to power it up

Hello, its the same thing. Almost everytime when I clean my desktop of dirt and the memory stick got moved. When I power up the unit and only the fan and led comes up.

My first suspect will always the memory. I will just make sure to clean the memory connector using pencil eraser method., reseat and power up again.

In your case I suggest to clean its connector to free it of dirt (varnish like coat on the memory connector). If it still freeze, check the memory if one is already failing.

SOURCE: Compaq Presario S4020WM

You need all the supported motherboard drivers (eg: PCI Bridge...) as you can see by the image of my Device manager screen there are MANY motherboard driver. Goto manufacturers web site... You should be able to get them.

SOURCE: HP Compaq Presario SR1250NX PC , will not turn

If no lgihts, sounds or anything at all, more than likely power supply.