Good evening, hopefully you can point me in the right direction. A friend of mine has got me to look at her Aspire T3-710, and from what I've gathered her son tried to install a new video card while the machine was running

The second that I put power to the PC there is a continuous beep and no boot/ black screen. First thing I done was remove the new video card in an attempt to boot via on-board graphics (No good). Checked all leads are connected properly. Remove and re-seat ram (Single 8gb stick). CPU fan is running fine. I've removed the MB battery for several hours, cleared CMOS. Tried ram from a working computer with still no luck. If I pull the 4 pin power from the board there's no solid beep, not that that's relevant I guess.
I'm thinking the board is fried, unless there's anything else you can suggest? Now if a motherboard was a few pennies I'd buy one and try it but unfortunately they seem to make £100 + second hand which is a bit ludicrous. Plus I'd be unlucky enough to do someone a favour and try and fix their computer and end up spending £100 and not fixing it
Is there an equivalent branded board on the market? Any suggestions welcome
Regards