I have an ATI Radeon HD 5700 card which i've been using under fully updated windows 7 with its latest drivers.
My monitor is a 2004 NEC LCD1703M which despite being pretty old runs fine. A friend gave me an IIYAMA ProLite E1900WS monitor (2009 or 20010 ). Both monitors are vga only. I've been using a DLDVI to VGA adapter to connect my old monitor and tested the same adapter to the new monitor and it worked fine.
So I bought an HDMI to vga adapter with the purpose of having a dual monitor setup. But when both screens are connected to the card the following problem occurs: The monitor connected to the hdmi port cycles between sleep and a black screen while the other shows the operating system for about two seconds before getting black for another two seconds. I can "use" the computer (move the mouse,click,type e.t.c.) while this happens but its not something pleasant.
I tried reinstalling the driver, booting with both screens connected (in which case the powerup messages and the bios are mirrored in both screens until I get to the login screen where everything falls apart)
Funny thing is, everything works if I disconnect the ATI graphics card and use the onboard intel one.
So, any suggestions as to what might be the problem and how I can fix it?