X86 device, which network chip should be chosen for "headache-free" functioning?

Well, this quad port Realtek card is really to be avoided.
First test :
ETH0 = WAN = Intel I219 Nic
ETH1 = LAN = Realtek R8111h Nic

"Hadrware unit hang" during the uploading test...the Nic didn't want to initialize i had to reboot the PC.

Second test :
ETH4 = WAN = Realtek R8111h Nic
ETH1 = LAN = Realtek R8111h Nic
it works but i can hardly reach 844Mbps.
image

The card is a PCIe 1.1 this is probably one of the reason ? idk

i also tried with SW offloading enabled, here is the result, it hardly reached the 940Mbps :
image

In both tests the cpu load on 2 cores went up to 43%, the others were around 15/20%

maybe i could try another driver for this Nic (RTL8111H) ??

root@OpenWrt:~# ethtool -i eth2
driver: r8169
version:
firmware-version: rtl8168h-2_0.0.2 02/26/15
expansion-rom-version:
bus-info: 0000:04:00.0
supports-statistics: yes
supports-test: no
supports-eeprom-access: no
supports-register-dump: yes
supports-priv-flags: no
root@OpenWrt:~#

The card Specs :

Specification

• Integrated 10/100/1000M transceiver
• Supports Giga Lite (500M) mode
• Auto-Negotiation with Next Page capability
• Supports PCI Express 1.1
• Supports pair swap/polarity/skew correction
• Crossover Detection & Auto-Correction
• Supports 1-Lane 2.5Gbps PCI Express Bus
• Supports hardware ECC (Error Correction Code) function
• Supports hardware CRC (Cyclic Redundancy Check) function
• Transmit/Receive on-chip buffer support
• Supports PCI MSI (Message Signaled Interrupt) and MSI-X
• Fully compliant with IEEE802.3, 802.3u and 802.3ab
• Supports IEEE 802.1P layer 2 Priority Encoding
• Supports 802.1Q VLAN tagging
• Supports IEEE 802.3az-2010(EEE)
• Supports Full Duplex flow control (IEEE.802.3x)
• Supports jumbo frame to 9K bytes
• Supports quad core Receive-Side Scaling(RSS)
• Supports Protocol Offload(ARP&NS)
• Supports Microsoft WPI (Wake Packet Indication)
• Wake-On-LAN and "RealWoW"Technology (remote wake-up) support
• Supports ECMA-393 ProxZzzy Standard for sleeping hosts