New monitor prevents Windows from starting

[Brendanhagen]

Computer and Windows start up fine with 7-8 yr old monitor. I purchased a new monitor (went to 24" lg gaming monitor from a low resolution sceptre monitor) and the computer seems to boot fine but I never get a signal to the monitor. (Lights, fans, peripherals all come on but "no signal" display)

I am running Windows 7 with dual AMD Radeon R9 270X cards in Cross-Fire configuration. HDMI output from master card with an HDMI to DVI adapter on the old monitor (since it has no HDMI input) and trying HDMI out from card to HDMI in on ew LG monitor.

The kicker is that if I start the computer with the old monitor and get into Windows, I can unplug the old monitor and plug in the new monitor and it works fine. This tells me it is a problem with the Windows startup sequence /vs/ the new monitor. I think...

What I've tried so far:
-All drivers updated for monitor and graphics cards
-Flashed newest version of BIOS
-Unseated and reseated RAM sticks (consequently caused a boot loop that was fixed with new slot placement of second RAM stick, talk about panic!)
-Unplug power cable and hold power button for both 30 seconds and 1 minute
-Setting both "attach.resolutionx/y" and "default.resolutionx/y" to new monitor specs (1920x1080) in three locations under Video in system configuration menu
-Pressing (also pressing and holding) CMOS Reset button on back of tower

Could it be that the new HDMI straight connection rather than the old HDMI to DVI is tripping up windows in the startup? Do I need a newer version of Windows? Some other option in the startup/boot sequence to change? Help!

Computer was built by a friend a few years ago and given to me, but here are the specs I have determined so far:

OLD MONITOR: 19" Sceptre
NEW MONITOR: 24" LG 24MP59G-P
Intel core i5 3.3 2500
ASRock mobo
AMD Radeon R9 270X (x2 in crossfire configuration)
16g RAM (2x8g Corsair)
Windows 7 SP1
Logitech keyboard(older, generic)
Razer Mamba
Razer Orbweaver

 

[Saturnity]

You should try plugging both of them in at the same time, like a dual monitor setup, and see if your computer can even identify or detect that there is something else plugged into it.

 

[Brendanhagen]

Unfortunately I didn't have the cables to try that at the time. I have however found a solution! I started the computer with the old monitor, then went into Device Manager and Uninstalled the Monitor showing. I also disabled the onboard graphics and a faulty Realtek Audio Controller. Then I swapped cables over to the new monitor, rebooted, and it works! I feel silly that I was trying everything but something so easy, even reading windows programming code! I hope this solution helps anyone else experiencing the same issues!

 

[verzigot]

hi, I have the same problem, "monitor entering power saving mode shortly", I try your solution but not works, you can help me?

 

[Brendanhagen]

hi, I have the same problem, "monitor entering power saving mode shortly", I try your solution but not works, you can help me?

I actually started having issues again. The old monitor working again and. Re monitor preventing the post and startup. Last thing I did (should have been first) was look at how my connections are:
-Old monitor was HDMI out from gpu with an HDMI to DVI adapter at the monitor.
-New monitor was Straight HDMI from gpu to monitor.

Because of no DVI in on the new monitor I used the old monitors adapter at the gpu, so DVI out from gpu and adapted to HDMI in at the monitor. With this setup the new monitor works and computer boots no issue, even displaying the post on the new monitor.

Combined with some other research I believe this is some internal setting with the gpu, only outputting a DVI compatible signal, so that the straight HDMI just wouldn't work and kept it from booting.

I would try different cables and each different display output/input combination you can and see if that works!