Question Network not staying connected.

[modemproblem101]

As the title says, my Desktop PC (Windows 7) is having problems staying connected or even detecting the Network even though it's using an Ethernet cable (And no, the cable is not messed up, it's fine, I've checked it.), but other devices like phones and laptops that use WiFi work perfectly.
What fixes the problem for me (temporarily) is going to "Network and Sharing Center" > "Change Adapter Settings" and then I right click the adapter and click Disable, then I click Diagnose, that solves it most of the times (sometimes it doesn't and I have to restart the PC.)
Help is appreciated as this is very annoying!

EDIT:

1. Specs: ECS H61H2-M10 Mobo, i5 3340 @ 3.1 GHz (x4 CPUs), 8 GB RAM, WDC WD10EZEX-00WN4A0 ATA HDD (Mostly Chinese parts)
Network Adapter: Qualcomm Atheros AR8152/8158 PCI-E Fast Ethernet Controller (NDIS 6.20)
Network card is built into the motherboard.

2. Only one network adapter is enabled.

3. Already installed the proper drivers from the manufacturer's website.

4. I have direct connection: router --> ethernet cable --> PC

 

[Ralston18]

Update your post to include full system hardware specs and be sure to include the wired network adapter: make and model.

First, verify that only one network adapter is enabled on your Desktop PC. Either wired or wireless - not both.

Second, download, reinstall, and reconfigure the wired network adapter's drivers. Do so via the manufacturer's website. Ensure that you download the applicable Windows 7 driver.

Third, the cable may be okay provided that there is a direct connection between Desktop PC and router. However, if there are other components such as switches, wall jacks, powerline adapters between Desktop PC and the router then any such component could be the cause of the disconnections.