Dell Dimension 2400 won't power up

[dario03]

My sisters old Dell won't power up at all. I plug it in and I get the green led light on the mobo like I should, but I also get a flashing amber light on the front led once I press the power button. I've tried unplugging everything but the mobo and I get the same results. So I'm guessing its the psu or mobo (maybe power button but doubt it). When I get a chance I'll try a different psu but I'm wondering if anybody was familiar with this problem or had another thought on what the problem could be.

 

[joeten]

have a look at cpu fan and a look here for some info Dell Dimension 2400 -- Won't Power On