OK great try the following settings:

DefaultReceiveWindow = 384000

DefaultSendWindow = 16384

DisableAddressSharing = 1

InitialLargeBufferCount = 100

InitialMediumBufferCount = 240

InitialSmallBufferCount = 320

LargeBufferSize = 81920

MaxFastTransmit = 64000

MediumBufferSize = 15040

PriorityBoost = 0

SmallBufferSize = 1280

TransmitWorker = 32

FastSendDatagramThreshold = 4096

EnableFastRouteLookup = 1

EnablePMTUDiscovery = 1

IgnorePushBitsOnReceive = 0

GlobalMaxTcpWindowSize = 64240

MaxFreeTcbs = 8000

MaxHashTableSize = 16384

MaxNormLookupMemory = 5000000

SackOpts = 1

SynAttackProtect = 1

Tcp1323Opts = 0

TcpLogLevel = 1

TcpMaxDupAcks = 2

TcpMaxHalfOpen = 100

TcpMaxHalfRetried = 80

TcpRecvSegmentSize = 1460

TcpSendSegmentSize = 1460

TcpTimedWaitDelay = 30

TcpUseRFC1122UrgentPointer = 0

TcpWindowSize = 64240

MaxConnectionsPer1_0Server = 20

MaxConnectionsPerServer = 10

DefaultTTL = 64

DisableUserTOSSetting = 0

TcpMaxDataRetransmissions = 6

DefaultTOSValue = 92

Your caps are 3000/128 so see how those settings work for you and let me know.