Maximus VII Ranger doesn't boot with Strix GTX980

[FernandoXP]

The error message on board is 77. But sometimes (once every ~50 attempts) it boots!
MB works great with other card in same slot and Strix works perfect on other MB. CPU is i7-4790k.
Is this problem known, or I have simply bad luck?

[Nahrga]

What was the other graphics card you have tried? and what PSU do you use?

One thing you could start out with is to clear CMOS (use the CLR_CMOS button at the bottom of the motherboard).

[FernandoXP]

Today I noticed that PC doesn't boot only when the output from graphic card is through Display Port cable. When the cable is disconnected and card outputs through DVI cable - everything works stable. Later today I am going to check the card with different DP cable. Do you think the cable may appear to be a reason for trouble?

[Nahrga]

No, I don't believe the cable is the only cause of your boot problems since you get Q-Code 77.
Did you use DP with the other GPU you tried? and what is your current motherboard BIOS version?

You should maybe try to update BIOS since this actually could be motherboard related.

[sebastianep]

I experienced the same with a 780 TI via DP and LG 34UM65-P. Solution was to shut off the Display and wait until it had fully turned off. Turn it back on and it was fixed.

[FernandoXP]

Last night I changed the DP cable to sthe ame but different make, and - surprise - the card works OK now! Came back to old cable and same error message "77" returned. Today I will check the suspected cable on other card. Strange, but looks it was the cable on the output that was the reason for thies fault.

[Nahrga]

I've never heard about a display cable causing Q-code errors, I guess it could be possible somehow.. This is strange indeed.