Note that if you use UEFI to boot, the correct command to regenerate grub is:

grub2-mkconfig -o /boot/efi/EFI/clearos/grub.cfg

Running the other command won't have harmed anything, but won't help either.

Well it looks like all is well now. Thank you so much for the help.

It worked like a charm and a lot better than this one:
https://forums.servethehome.com/index.php?threads/patching-intel-x520-eeprom-to-unlock-all-sfp-transceivers.24634/

Maybe it will help someone else if yours does not.....but I choose your way.
Thanks again!

So what about the output I asked for?

I really appreciate you sticking with this but I am still getting the same response.

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: em1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
link/ether 4c:d9:8f:9f:d9:3f brd ff:ff:ff:ff:ff:ff
3: em2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
link/ether 4c:d9:8f:9f:d9:40 brd ff:ff:ff:ff:ff:ff

04:00.0 Ethernet controller: Broadcom Inc. and subsidiaries NetXtreme BCM5720 2-port Gigabit Ethernet PCIe
Subsystem: Dell Device 001f
Kernel driver in use: tg3
Kernel modules: tg3
04:00.1 Ethernet controller: Broadcom Inc. and subsidiaries NetXtreme BCM5720 2-port Gigabit Ethernet PCIe
Subsystem: Dell Device 001f
Kernel driver in use: tg3
Kernel modules: tg3
--
65:00.0 Ethernet controller: Intel Corporation Ethernet 10G 2P X520 Adapter (rev 01)
Subsystem: Intel Corporation 10GbE 2P X520 Adapter
Kernel modules: ixgbe
65:00.1 Ethernet controller: Intel Corporation Ethernet 10G 2P X520 Adapter (rev 01)
Subsystem: Intel Corporation 10GbE 2P X520 Adapter
Kernel modules: ixgbe
b2:05.0 System peripheral: Intel Corporation Sky Lake-E VT-d (rev 07)

Hmm. I was looking at the wrong PCI ID. I should have been looking at [8086:154d] and the built in module should have been OK, but there is no harm with the kmod one. Curious that it is still not loading.

What happens if you do a:

modprobe -v ixgbe

Then the output from

ip link

lspci -k | grep Eth -A 3

This may take a bit of googling.

Nick, thanks again but no such luck. There is no change and after a reboot the card is still not available. The card is on pcie riser, any chance that is the issue? I had seen something like that in the past with a raid card and Untangle but I was able to get around it.

65:00.0 Ethernet controller [0200]: Intel Corporation Ethernet 10G 2P X520 Adapter [8086:154d] (rev 01)
Subsystem: Intel Corporation 10GbE 2P X520 Adapter [8086:7b11]
Kernel modules: ixgbe
65:00.1 Ethernet controller [0200]: Intel Corporation Ethernet 10G 2P X520 Adapter [8086:154d] (rev 01)
Subsystem: Intel Corporation 10GbE 2P X520 Adapter [8086:7b11]
Kernel modules: ixgbe
b2:05.0 System peripheral [0880]: Intel Corporation Sky Lake-E VT-d [8086:2034] (rev 07)

What that is showing you is that there are no lines "Kernel driver in use" so it has not picked up a driver. From the NIC name and your output, the driver required is the ixgbe, but if you do a "modinfo ixgbe" it does not show compatible PCI ID's (8086:7b11). Also modinfo shows the driver is quite an old version compared to Intel's site. Compiling drivers from source is not so neat as they need to be recompiled for every kernel update. Fortunately there is a group called ElRepo who maintain a bunch of drivers with a slight modification so they try and survive a kernel update. You can get the ixgbe-kmod driver from one of their mirrors like here. Either set up their repo and install it from there, or just download it and install it locally:

wget http://elrepo.reloumirrors.net/elrepo/el7/x86_64/RPMS/kmod-ixgbe-5.6.3-2.el7_7.elrepo.x86_64.rpm

yum install kmod-ixgbe-5.6.3-2.el7_7.elrepo.x86_64.rpm

Then it may just work or you may need to reboot to bring it into use.

The driver should not need updating through all the ClearOS 7.7 line. It may or may not survive if 7.8 comes out. We won't know until the kernel is released. If it won't survive the upgrade, ElRepo should re-release it.

Nick, thank you for your help. I must warn you, I am a Windows guy. I don't usually get under the hood / bonnet of Linux unless I have to.

04:00.0 Ethernet controller [0200]: Broadcom Inc. and subsidiaries NetXtreme BCM5720 2-port Gigabit Ethernet PCIe [14e4:165f]
Subsystem: Dell Device [1028:001f]
Kernel driver in use: tg3
Kernel modules: tg3
04:00.1 Ethernet controller [0200]: Broadcom Inc. and subsidiaries NetXtreme BCM5720 2-port Gigabit Ethernet PCIe [14e4:165f]
Subsystem: Dell Device [1028:001f]
Kernel driver in use: tg3
Kernel modules: tg3
--
65:00.0 Ethernet controller [0200]: Intel Corporation Ethernet 10G 2P X520 Adapter [8086:154d] (rev 01)
Subsystem: Intel Corporation 10GbE 2P X520 Adapter [8086:7b11]
Kernel modules: ixgbe
65:00.1 Ethernet controller [0200]: Intel Corporation Ethernet 10G 2P X520 Adapter [8086:154d] (rev 01)
Subsystem: Intel Corporation 10GbE 2P X520 Adapter [8086:7b11]
Kernel modules: ixgbe
b2:05.0 System peripheral [0880]: Intel Corporation Sky Lake-E VT-d [8086:2034] (rev 07)

What do you get from:

lspci -knn | grep Eth -A 3