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Thank you for taking the time to provide the routing tables and network topology

From the information you shared, having two NICs on different subnets is not necessarily the problem. The main thing I would look at is the routing configuration and DNS resolution.

Windows first uses the most specific route that matches the destination. When there are competing routes with the same prefix length, the route and interface metrics help determine which path is preferred.

In your setup, the intended configuration appears to be:

• 192.168.1.0/24 NIC: local network access
• 192.168.0.0/24 10-Gbps NIC: Internet access
• The 192.168.0.x NIC: default gateway for Internet traffic

1. You should not need a static route for 192.168.1.0/24

On the laptop, you already have this route:

192.168.1.0 255.255.255.0 On-link 192.168.1.6

This is important because it tells Windows that 192.168.1.0/24 is directly reachable through the NIC with address 192.168.1.6.

Therefore, traffic from 192.168.1.6 to 192.168.1.3 should go directly between those interfaces. It does not need to pass through the 192.168.1.1 router.

Unless 192.168.1.1 is needed to reach a different subnet, such as 192.168.2.0/24, I would remove the manually added route for 192.168.1.0/24.

2. Check the laptop's two default routes

One thing that stands out in the laptop's route table is that there are still two default routes:

0.0.0.0/0 -> 192.168.1.1 metric 30

0.0.0.0/0 -> 192.168.0.254 metric 25

Even though you mentioned that the 192.168.1.x NIC does not have a default gateway configured, the routing table still shows a default route through 192.168.1.1.

I would verify where that route is coming from and remove it if it is not required.

For the design you described, I would aim for the following configuration:

LAN NIC (192.168.1.x)

• IP address: 192.168.1.x/24
• Default gateway: None
• Internal DNS as required

10-Gbps/Internet NIC (192.168.0.x)

• IP address: 192.168.0.x/24
• Default gateway: 192.168.0.254
• Used as the default route for Internet traffic

Afterward, check route print again and confirm that you have only the intended default route through 192.168.0.254.

3. NIC priority alone should not determine local subnet traffic

I would not focus too much on making one NIC "priority 1."

For example, when the laptop sends traffic to 192.168.1.3, Windows already has a specific 192.168.1.0/24 on-link route. That route is more specific than the 0.0.0.0/0 default Internet route.

So, the expected behavior is:

192.168.1.x traffic -> 1-Gbps LAN NIC

Internet traffic -> 10-Gbps NIC -> 192.168.0.254

Interface metrics become particularly relevant when Windows has multiple routes that are otherwise valid candidates for the same destination.

4. Check DNS

The screenshots suggest there may be a second issue involving name resolution.

For example, if you run:

ping desktopname

And the name resolves to 192.168.0.182 instead of 192.168.1.3, Windows will ping the address returned by DNS. Changing the interface metric would not make the hostname resolve to the other address.

I would compare:

nslookup desktopname

With:

ping 192.168.1.3

If ping 192.168.1.3 works but ping desktopname resolves to the 192.168.0.x address, then I would investigate the DNS records and DNS registration of the two adapters rather than adding more static routes.

5. Suggested configuration

Ultimately, I would try to get the routing table to follow this design:

192.168.1.0/24 -> directly connected 1-Gbps NIC

192.168.0.0/24 -> directly connected 10-Gbps NIC

0.0.0.0/0 -> 192.168.0.254 through the 10-Gbps NIC

If another internal subnet such as 192.168.2.0/24 really is reachable through the router at 192.168.1.1, then a specific route for that remote subnet would make sense, for example:

route -p add 192.168.2.0 mask 255.255.255.0 192.168.1.1

After making the changes, I would verify the behavior with:

route print

ping 192.168.1.3

tracert 192.168.1.3

nslookup desktopname

I would start with the direct IP ping because it separates a routing problem from a DNS/name-resolution problem.

The most important detail from the information you posted is that the laptop still shows a default route through 192.168.1.1, despite the intention for that NIC to have no default gateway. I would investigate and clean up that route first, then verify DNS registration if communication by hostname still uses the 192.168.0.x address.

I hope this helps clarify what is happening with the two adapters.

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