So everything was just working fine when I left my house and get a new HDMI to DVI cable(since I heard it displays nicer than the standard VGA cables which I have been using). So when I got back to my house, the computer was still displaying normally. Then I decided to switch the cables so I could get to take a look at the difference before I head out to bed. When I have disconnected the VGA cables and connected the HDMI(input) to DVI(output) cable, nothing was displayed so I though oh that's fine, I will just have to replace the cable. Then when I disconnected the HDMI to DVI and reconnected the VGA cable my computer was obviously still on but nothing was displaying. I turned it off my shutting it down with my keyboard(blind shutdown) and when I turned it back on it was still not displaying. I tried the monitor on another computer and the monitor works but when I tried another monitor to the computer, it still isn't displaying anything. The computer turns on fine(I can hear the windows sound) but no display. I've also tried multiple VGA cables and HDMI to DVI cables so it's not the cables that have the problem. Also when I disconnect the cable from the computer to the monitor, it says "check signal cable" as expected but when I reconnect the cable, it kinda detects the computer but it seems to go to sleep mode(power light blinking) I have pressed buttons both on mouse and keyboard but still nothing. I really need help! The computer and monitor are ney and pretty expensive. BTW as much as possible I don't wanna take it to the shop cause I don't want my mom to know about the problem. But I will if I really can't self-remedy this.
Monitor: SyncMaster S23B300 LED
intel i7-3000 processor
Radeon HD 5670
Motherboard: Asus P8Z77-VLK