try to disconnect absolutely everything from the Board and remove the CMOS Battery. leave it alone over night. next day connect only necessary cables (24 pin and 8 pin PSU) and try to boot. it should start to beep because of the missing RAM.

if it fails to boot, your Board is dead.

Hello, Thank you for your reply. Just to confirm that I've interpreted this correctly the CPU and GPU must be disconnected? Think this is what you're saying but I'd wanted to double check. Does a Mainboard not need a functioning CPU to issue beep codes? At a guess probably not. Excuse my ignorance please. Appreciate your reply though. Will advise whether or not this works. Should there be no beep codes does this generally mean that the BIOS is dead and needs replacing? Considering fans spin up and the CPU starts to get warm I'm thinking down the lines of the Mainboard is trying to power up successfully but without knowing what power rails are / aren't working etc. understandably I've no idea what's going on. Would consider trying to replace the BIOS should this be worth a try. Aware it's probably SMD though.

yes. take everything out. also take a look at the CPU Socket. is it okay? no bent Pins or dirt?

Edit:

most of the time if the CPU is not working the Board should give you a Beep Code. but sometimes the PC just won't boot. but we already know that your CPU is fine since you already tried different one.

Hi, Thank you for confirming what needs to be taken out from the Aurora R4 Mainboard. Was confused as I'd thought that a Mainboard could not generate beep codes without a CPU being present but I'm not 100% certain about that. I'm not entirely convinced that the CPU pins are as they should be and think there are some slightly bent one's. Already tried to bend some of them back into position but admit this is extremely fiddly without the appropriate tools. Attached is a photo of the LGA2011 socket 'as is' to to speak. Was worried that I'd 'cooked' the CPU as put this back into another Aurora R4 this-morning and that would not boot either. Anyway - After re-seating the CPU into its socket it'd powered back up again successfully. Do you have any recommendations on how to go about bending pins back into position please? At a guess could check for some Youtube videos on this.

The faulty Aurora R4 Mainboard has been switched off for about 6-8 hrs and I'd tried to determine whether any beep codes were generated and the Sys Fan 2 spinned along with Sys Fan 1 which subsequently stopped, stalled for 30-secs approximately and then began spinning again but - granted you've advised leaving the Mainboard in a powered-down state for 24-hrs which is something I'll definitely try.

Can confirm CPU, GPU, RAM, CMOS battery, ATX Power Connector, CPU Power Connector disconnected and the clear CMOS jumper has been changed from position 1-2 to position 2-3 (this is confusing also as the silk-screening say's the CMOS clear jumper needs to be put into position 3-4 but I've no idea what position 3-4 is).

The Password jumper is in position 2-3 (not sure whether this has any affect on the contents of the CMOS).

Thanks again for your help.

Would really like to get this rig back up and running but think the Mainboard could be dead as you've said.

PS The photo illustrating the CPU Socket was taken shortly after I'd sprayed the Mainboard with Air-Duster hence the SMD components that are centered in the CPU Socket appear to have moisture on them. Not entirely convinced whether there is a missing pin on the inner edge of the top right of the CPU Socket. Uncertain should this have an impact on whether the Mainboard boots but at a guess it's having an impact. The pins over-all seem to look 'okay' but I'm no expert on this by any means.

Sounds like a bad motherboard.
 
Like CarbonBasedLifeform says ... machine must be a basic as possible.
 

Alienware Desktop - General Hardware Troubleshooting 

Also, Intel processor on Aurora-R4 will NOT run without a cooler of some kind (not even for a few seconds). It might not even BIOS Post without a cooler. If you don't want to bother with installing a fan cooler, but DO want to disconnect MIO-Board, you can use Anti-MIO mod for testing:

Hello,

Thank you for your reply and for the troubleshooting URLs - Very informative.

Will try and post back here with any progress that has been made (should any progress be made).

Thanks again to CarbonBasedLifeform and Tesla1856 for your fault finding suggestions - they are much appreciated.

< Not entirely convinced whether there is a missing pin on the inner edge of the top right of the CPU Socket.

I doubt it. However, you can look on the chip itself for the proper pattern in the area.

I've never heard of trying to run a Motherboard without a CPU installed.
 
I don't think I would mess with the processor socket pins much, if at all. Maybe some plastic-safe contact cleaner?
 
It sounds fried to me ... at least you have the other machine to use. IIRC, Aurora-R4 was X79 chipset and socket 2011. Motherboards (Dell or even retail after-market) shouldn't be too expensive if you must repair it.

i never said you should boot without the CPU. i remember typing the line "put it back in next day" but then i deleted it because i thought you already know that. besides, you tried to boot your other working machine after you messed up installing the CPU and it didn't boot either. which actually answers your question.

MOISTER? how did that happen? make sure the components are super dry before you turn the PC on. otherwise you will short out the board. next time you're using compressed air to clean your PC you should not tilt the Bottle. hold it vertically.

Tesla1856 posted a link which says that the Board will not post without CPU Cooler/Mio Board. which meens you should install an air cooler or connect the MIO Board together with the Pump. Tesla already explained that part.

ignore the jumper stuff. you already pulled the CMOS Battery multiple times which does the same.

here is a working LGA 2011 Socket. took me 5 seconds to google the image:

your Socket looks okay to me. for the future you shouldn't mess with it yourself. you can google for repair service. usually it costs around 30$ to fix the socket.

step by step:
1. make sure the components are completely dry.
2. install the CPU. don't forget to apply the Thermal Paste. Arctic Silver 5 is a great choice.
3. install an air cooler or connect the MIO Board and the Watercooler.
4. connect the PSU cables. only 24 pin and CPU 8 pin cables.
5. try to boot. if it beeps then the BIOS ROM is still alive. if not buy a new motherboard on ebay for 320$ or replace it with an aftermarket Board.

Hello,

Thank you for your reply. Wasn't sure whether you'd suggested trying to boot with / without a CPU and did get confused admittedly. Considerable care was taken to ensure correct orientation etc. but for reasons unknown it'd not boot prior to the CPU being taken out and put back in again. Aware not to power up a Mainboard nor any consumer electronics that show any signs of being wet/damp but thanks for the advice on how to correctly use an air duster rattle-can (was unaware of this).

Not being based in the US I'm unaware of a repairer that could replace a CPU socket for about $30 nor anything near this but hopefully the CPU pins are okay. Confused that none of the VRM circuitry seems to get warm/hot with a CPU plugged into the Mainboard. Some of the CPU pins were definitely bent prior to the photo of the CPU Socket being taken and uploaded on here but without specialist tooling etc. at a guess it's extremely difficult to perform a CPU Socket repair.

would not pay $320 to replace the Mainboard like for like and cannot afford to either (would prefer to spend that sort of money on a newer generation Mainboard and CPU) but again thank you for the suggestion.

very informative thread and forum.