Why does 1C 7.7 work on a new server with Win Server 2012R2 slower than on the old one from 2003?

Question

1C

Good afternoon!
We have the following situation:
1C 7.7 is running on a server with the following characteristics:

• MB: SuperMicro X7DWA-NO Xeon 2xLGA771/i5400v/8xDDR2/6xSATA/E-ATX
  
• CPU: Intel Xeon 2.5GHz
  
• RAM: DDRII 2Gb (PC2-6400) CL5 ECC Kingston KVR800D2D8F5/2G x 2pcs (4Gb)
  
• HDD: WD 640.0Gb WD6400AAKS SATAII 7200rpm, 16Mb x 2pcs
  
• OS: Windows Server 2003
  

We want to transfer 1C to another server with the following characteristics:

• MB: SuperMicro X9DR3-LN4F+
  
• CPU: Intel Xeon E5-2630 V2 2.6GHz (6 cores)
  
• RAM: Kingston KVR16R11S8-4HB x 4pcs (16Gb)
  
• HDD: Western Digital WD RE 1TB WD1001FYYG SAS x 2pcs
  
• OS: Windows Server 2012R2
  

On both servers, using Windows, HDD mirroring is installed, except for 1C, in fact, there is nothing. According to the CrystalDiskMark HDD speed test, the write and read speed on a server running Windows 2012R2 is 1.7 times faster than a server running Win2003.
At the same time, 1C works much slower on a server from 2012R2 than on a server from 2003. For example, they launched a lot of processing to close registers: on a server from 2012R2, the execution time took more than 3 hours, on a server from 2003 - only one and a half. 1C DBF-th, fully works on the server (we connect via RDP).
Sources found in Google connect what is happening with disabled caching on the HDD in raid1, but, as far as I understand, we do not have RAID, and mirroring occurs using Windows tools (please correct me if I'm wrong).
Thus, the essence of the question is the following: why does 1C 7.7 work much more slowly on a more powerful server with Windows Server 2012R2 than on a less powerful one with Windows Server 2003? Where to dig to fix it?
Thanks for reading and replies!