Which motherboard to choose for a host for hyper-v?

Question

motherboards

Advise the motherboard under the server for virtual machines.
Approximate usage parameters:
Host axis: Windows Server 2008 R2
Virtualization: Hyper-V
Virtual machines: 4 pcs. as of Windows Server 2008 R2, all are terminal servers. ~20 users per machine, i.e. only ~70-80 people at the same time.
The main tasks of users: 1C, office.
The budget for the entire server is ~30-35 thousand.

Answer 1

Selection result:
9710.00 Intel Core i7-3820 processor, 3.60GHz, 10MB, LGA2011, OEM
1320.00 Zalman CNPS11X Performa cooler, Socket 775/1156/1366/2011/AM2/AM3/FM1
3960.00 ATX 650W power supply
Corsair TX650M Active PFC Fan 14
cm
computer memory DIMM DDR3, 32GB (4x8GB), PC3-12800, 1600MHz, Corsair Vengeance Pro black, CMY32GX3M4A1600C9
-------------
40300.00
they are already in stock, so a more expensive mother, processor and power supply are taken.
As a result, the budget was exceeded by 5 thousand due to the amount of memory, which was originally planned at 16GB (7060.00), and 32GB (13070.00) was chosen.
Although there are already cases with a PSU, it was decided to take a new one because of the larger CPU cooler and more powerful PSU.
Perhaps something better could have been picked up for the same money, but in general the issue was resolved quite well in my opinion.
Special thanks to @Masterme for the cpubenchmark.net cpubenchmark.net cpubenchmark.net tip about the processor and its price/speed ratio
Update: Windows server 2008 r2 is not officially supported for this motherboard. Under it officially there are no drivers, in particular for a network card.
However, there are solutions on the Internet that allow you to modify inf with a simple "copy-paste" and the network driver installs perfectly.

Answer 2

for such money only a desktop. take ASUS P8H77V-LE, i5 or i7 processor for it, 4x8 RAM.

Answer 3

In my "sponsored farms" as a budget platform, a bundle of AsRock Z77 Pro4-M (~ $ 95) and Intel Xeon E3-1230V2 (~ $ 240) is used for such purposes. There are 15-17 such sets of pieces, in work for 10-12 months, the flight is normal.
Memory Hynix 8 GB DDR3 1600 MHz, 4 sticks each. But it was bought for another $45, now it will be about twice as expensive.
Well, reliable nutrition is the basis of everything.