You don't need a hdd to get a signal to the monitor.
Are you sure the monitor and cable function?
Replace the cmos battery....cheap test.
I have this old computer , a Asus CM1435 , i used it for gaming a while ago and i want to make it functional again. I had a GPU (GT 640) and everything was working great. A few years later, i build a high-end pc and left that one alone. I sold the GPU to a friend since i didn't use this one. I want to use it again to watch streams in my bedroom. Anyway i don't have a gpu in it and i tried starting it but there is no signal. I did a CMOS reset on the motherboard but still no signal. Another problem is, i removed the hardrive and store it in a closet with other hardrives, of the same company. So i tried doing the reset and trying each hardrives one at the time and still no signal. Any suggestions to my problem ?

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