I've just bought a BenQ GL2450HM 24" Screen and tried to hook it up to my freshly build PC but when I try connecting HDMI to HDMI from the monitor to GPU (Sapphire R9 290) it comes up with the message "HDMI No Signal Detected!". I haven't got a DVI to DVI cable but I've got a HDMI to DVI cable which I've tried with also the same results. I have also tried plugging it into my motherboard's integrated graphics card and still not signal detected. Could there be a problem with the monitor or could it be that I made a mistake whilst building it.