Hyper-v and very slow network

Question

Dear all,
I have a big problem with my hyper-v server and network card. I've found a lot of topic around this question but none of them helped me.
I have a Win 2008 R2 Server with only Hyper-V installed. I have 3 NIC , one is reserved to the host management and the others two are reserved for virtual machine .
All NIC are Intel, one is integrated on the Intel motherboard and the others are Intel Gigabit ET Dual port .
Before installing the role of Hyper-V all NIC worked perfectly with speed around 1Gb (file transfer average 90 MB/Sec, of course I have a Gigabit LAN) .
After Hyper-V install, the host system  is going very slow and the network file transfer using the dedicated NIC is about ten time slower (9-10MB /sec) . Same problem with all VM off and also if I remove all VM !
I tried all of suggestion found in old post (disabling TCP checksum / offload ...) but nothing happens.
What is really strange is that by removing all network card all the Host operating system seems to improve the speed... but, of course, I can't use  my LAN :(
I need help because every night I must make a full backup of Virtual hard disk from the host to a backup server in my lan.
My configuration:
- Server Win 2008 R2 SP1 with Hyper-V and no others role
- 2 Virtual Machine (one Win 2008 R2 and one Win 7 Ultimate)
- NAS Linux (access via SMB with no problem)
- Various Windows 7 Pro client
Thanks in advance to everybody,
Luca M.

Answer 1

I disabled the VMQ on the configuration of the HV physical machine, a LACP with 2 NICs, so i disabled on both.
Before, i tried to disable  VMQ on the Multiplex adapter (connected to the vswitch and dind´t worked
The ping times drop form 200ms to 6ms, normal in my environment
Before and after:
PS C:\Users\Administrator> Get-NetAdapter -Physical | Get-NetAdapterAdvancedProperty | Where-Object "DisplayName" -Like "*queue*"
Name                      DisplayName                    DisplayValue                   RegistryKeyword RegistryValue
SLOT 1 Port 2             Maximum Number of RSS Queues   RSS 4 Queues                   *NumRssQueues   {4}
SLOT 1 Port 2             Virtual Machine Queues         Enabled                        *VMQ            {1}
SLOT 1 Port 4             Maximum Number of RSS Queues   RSS 4 Queues                   *NumRssQueues   {4}
SLOT 1 Port 4             Virtual Machine Queues         Enabled                        *VMQ            {1}
SLOT 1 Port 1             Maximum Number of RSS Queues   RSS 4 Queues                   *NumRssQueues   {4}
SLOT 1 Port 1             Virtual Machine Queues         Enabled                        *VMQ            {1}
SLOT 1 Port 3             Maximum Number of RSS Queues   RSS 4 Queues                   *NumRssQueues   {4}
SLOT 1 Port 3             Virtual Machine Queues         Enabled                        *VMQ            {1}
PS C:\Users\Administrator> Get-NetAdapter -Physical | Get-NetAdapterAdvancedProperty | Where-Object "DisplayName" -Like "*queue*"
Name                      DisplayName                    DisplayValue                   RegistryKeyword RegistryValue
SLOT 1 Port 2             Maximum Number of RSS Queues   RSS 4 Queues                   *NumRssQueues   {4}
SLOT 1 Port 2             Virtual Machine Queues         Disabled                       *VMQ            {0}
SLOT 1 Port 1             Maximum Number of RSS Queues   RSS 4 Queues                   *NumRssQueues   {4}
SLOT 1 Port 1             Virtual Machine Queues         Enabled                        *VMQ            {1}
SLOT 1 Port 3             Maximum Number of RSS Queues   RSS 4 Queues                   *NumRssQueues   {4}
SLOT 1 Port 3             Virtual Machine Queues         Enabled                        *VMQ            {1}
SLOT 1 Port 4             Maximum Number of RSS Queues   RSS 4 Queues                   *NumRssQueues   {4}
SLOT 1 Port 4             Virtual Machine Queues         Disabled                       *VMQ            {0}
PS C:\Users\Administrator> Get-NetLbfoTeam
Name                   : TeamMGMT
Members                : {SLOT 1 Port 1, SLOT 1 Port 3}
TeamNics               : TeamMGMT
TeamingMode            : Lacp
LoadBalancingAlgorithm : TransportPorts
Status                 : Up
Name                   : TeamVM
Members                : {SLOT 1 Port 4, SLOT 1 Port 2}
TeamNics               : TeamVM
TeamingMode            : Lacp
LoadBalancingAlgorithm : HyperVPort
Status                 : Up