First off try the new GPU in a different computer to see if it works.
Test your power supply, or try a higher wattage power supply.
Acer used an OEM motherboard for that model. It may be set to not allow component upgrades that the system can not recognize.
Go into the BIOS to see if you can turn off the secure boot. Then try to install the card. If it does not work you will need to check with Acer to see what cards are approved to use on your motherboard.
I tried using a 650w power supply with it, same thing happens. I would test the gpu in another computer but I unfortunately don't have another computer to test it in. I do know that the lastest BIOS update acer released for this motherboard was back in 2012, I have it now, same thing still. I looked in BIOS settings and also found no setting for secure boot.
Thanks for the reply though.