Intel motherboard not starting up - No POST, fans working

[thecoolone3]

As the title says, my computer's Intel motherboard isn't making any beeps (no POST) and the monitor isn't detecting any output. However, when I remove the computer's RAM, it beeps 3 times (memory error), so it must be working. I have tried clearing the CMOS but to no avail. After running for a few seconds without turning on, the fans adjust their speed automatically, so I think the BIOS is OK. The heatsink is firmly installed, and the CPU is definitely compatible. I even replaced it with another (compatible) CPU I had and it still didn't boot! The graphics card is onboard running through VGA. About 2 days ago it was booting Windows XP just fine. I created a new account for my sister, clicked restart, and it refused to POST. Any ideas? Thank you in advance, and sorry if I sound a little exasperated!
(Motherboard is an Intel DG41RQ if that helps)

 

[laviniuc]

you should try with a dedicated graphics card maybe something is wrong with the integrated graphics...

 

[thecoolone3]

you should try with a dedicated graphics card maybe something is wrong with the integrated graphics...

Unfortunately, the only discrete graphics card I have takes 2 power inputs, but this motherboard only has one output

As I said in my original post, the computer could boot into Windows XP just fine about 2 days ago, and the onboard card was working. Now it won't even post! I really don't want to give up hope on this machine...

 

[alexoiu]

Try testing different monitor/video cable.