Got a mystery problem and things don't look good.

I was gifted a GTX1070 and I stuck it in my old Frankenstein computer and all hell broke loose. Here's what went down.

>install card
>lights fans action
>boot to windows 7
>windows installs new drivers successfully
>mandatory restart
>attempts post, restarts
>total power failure
It will no longer start at this point. Hit the power and get a twitch from a case fan but that's it. Dead. This was a 500W psu.

>Install new 700W psu
>powers on
>get a quick double or triple beep then 8 beeps
>no display at all.
>no lights or fan activity on the card
Tried reseating the card, use different GPU power plug. No good.
>put old card in and everything is fine...

I can't tell if its a compatibility issues or somehow the card fried.

This is the system info:
Manufacturer: BIOSTAR Group
Model: A770E3
CPU Vendor: AuthenticAMD
CPU Brand: AMD Phenom(tm) II X4 965 Processor
Speed: 3400 MHz
4 logical processors
4 physical processors
Windows 7 (64 bit)
Driver: NVIDIA GeForce GT 740
Primary VRAM: 2047 MB
Audio device: Speakers (Creative SB X-Fi)
RAM: 32767 Mb
Miscellaneous:
UI Language: English
Total Hard Disk Space Available: 1953519 MB
Largest Free Hard Disk Block: 750185 MB
OS Install Date: Nov 16 2013