So is that the only solution ? Really, there isn't any motherboard available which is compatible now ? And BTW, I searched used too, but did not find. Can you help ? And cant I use the same processor and RAM in any other mother board ?
Yes, its seen already. He said, motherboard is dead and you need replacement. New motherboards are hardly 300-400 USD> Why would the old one be so expensive ?
Booting, working also. But it keeps on restarting again and again every 1-2 hours. So basically its not dead, but it restarts the PC again and again, frequently.
The SMPS 750w Cooler Master it has. We even changed that and still same issue, so I dont think PSU has the issue.
As long as the CPU socket is right and the MoBo will run at the speed of the CPU, you should be ok. Just make sure that the old RAM will fit in the slots and that the Mobo supports the RAM at its' max speed. You may, however, notice a slight decrease in performance. You won't know until you populate the board and get it running.
This sounds like a production computer in some sort of business or research facility. If that's the case, you might be better off getting/building an altogether new computer. Things do wear out and sooner of later (maybe the time is now) all equipment needs to be retired. I'm with Hadron-Curious on this. I can't speak to your tax laws, but in the good old USofA business equipment expenses can be "written off". When they reach their end of life, or if the repair cost is something like 60% of the original cost, the unit is taken off the books. Hopefully you can retain your software. If not then that portents the age of the equipment.
The Socket LGA2011 are 4-6 years old. Asus and Gigabyte had the most models at that time. If I remember right, both had the x79 series which were equipped with 8 DIMM slots. So, it should be possible to get a ***X79 MB used or even still a new one from a old stock! In Thailand it's easy to get 'broken' MB's repaired, we've a lot companies who doing that job. I would even get a used, if I would take the time to search in Bankok IT Centers for that! But, eBay would be a source for the OP to be able to get what he's looking for! From the technical point of view, those MB's are still not outdated yet. On the end of the day, it's only about how much the user will/like pay for it.