Power supply not enough power?

[baba001]

I hope you might have some insight I bought gtx 980 plug it to pcie x16 slot and power cables 2 of them press power and spark in one of them 6 pin power sparked I think card is dead oh well 150 down the sink I was hopping my dell is not dead plug in the previous card with old HD 7700 takes 55 volts while 980 274 volts and everything works fine computers still alive now I plugged in gtx again but nothing no power just power button flashing amber on dell 2blinks fallow by short pause 2 blinks long pause repeat this indicate bad power supply or motherboard I replaced mother boards and power supply I am thinking both power supply’s can be bad since computer is working fine with low end gpu. to summarize only low end gpu works fine amd fire pro works Fan shining to but looses screen after a minute screen goes crazy and looses screen nothing on screen while gtx no power To computer when press go power button and POWER On dell flashing

thanks guys

dell 7910 intex Xeon v4 8 core 16 go memory 1300 v power supply windows 10 pro gpu HD 7700 would like to install fire pro 7500 or gtx 980-Dell Precision Workstation T7910 Motherboard 2TPVG