1st and foremost i'm not too familiar with the internal workings of computers . The problem i'm having with my Compaq desktop computer is the orange light on the front comes on and stays on as soon as i push the power. No green light at all. My HD isn't spinning either and there are no beeps. I used different psus which were 50 watts lower(all i could find) to check if that was the cause, no luck. When I connected a smaller HD than the 1 I have, it spun up. The green light on the back of the psu comes on as well and the fan to the ps and processor work. It's driving me insane trying to figure out the cause, thats why im here. ANY possible solutions would be GREATLY appreciated!

of the top of my head, it could be the cpu and or motherboard .when the smaller harddrive spins does it try to load ,are you getting anything on the monitor

I don't believe it tries to load and the monitor stays in standby

assuming that the power supplies you used were good then im sticking with motherboard and or cpu.

I was afraid you were going to say that Thank you for the information.

yeah! it been my experience that when it boots like yours its usually the motherboard.but it could also be ram,or video card .,it could be a lot of things so you really need to trouble shoot by replacing thing with known working parts .a computer with nothing inside but a cpu and motherboard with video card, will still boot and show things on the monitor .

you will need a new computer if its the motherboard, and it isnt under warranty, as the HP ones are custom

or you could check e-bay for mother board for it .

I won't be able to replace the motherboard then??

I removed both sticks of memory and the orange light isnt coming on now either if that makes any difference in a possible cause.