Adjust Network Adapter Transmit Buffers in Regedit

Adjusting network adapter transmit buffer descriptors alters the amount of memory allocated for outbound packet queues, which can reduce packet loss and improve network throughput under heavy loads. While these settings are commonly accessible through the Device Manager, certain drivers only expose or allow overrides for these values via the Windows Registry. This guide provides the exact steps to locate your network adapter in the Registry Editor and modify its transmit descriptors.

Step 1: Open the Registry Editor

  1. Press Windows Key + R to open the Run dialog box.
  2. Type regedit and press Enter or click OK.
  3. Select Yes if prompted by User Account Control (UAC).

Step 2: Navigate to the Network Adapters Registry Key

Paste the following path into the address bar at the top of the Registry Editor and press Enter:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4d36e972-e325-11ce-bfc1-08002be10318}

Step 3: Locate Your Specific Network Adapter

Under the {4d36e972-e325-11ce-bfc1-08002be10318} key, you will see a list of numbered subfolders (e.g., 0000, 0001, 0002).

  1. Click on each numbered folder one by one.
  2. Look at the DriverDesc string value in the right pane.
  3. Identify the folder where the DriverDesc matches the exact name of your active network adapter (for example, Intel(R) Ethernet Controller or Realtek PCIe GbE Family Controller).

Step 4: Modify or Create the Transmit Descriptors Value

Once inside the correct numbered folder, search the right pane for the transmit descriptor key. The naming convention depends on your network adapter manufacturer:

If the value exists: 1. Double-click the entry to open the edit window. 2. Under Base, select Decimal. 3. Enter your desired buffer size (common supported values include 512, 1024, 2048, or 4096). 4. Click OK.

If the value does not exist: 1. Right-click in the empty space in the right pane. 2. Select New > DWORD (32-bit) Value (or String Value if your driver expects a string entry for parameter definitions). 3. Name it according to your driver specification (typically *TxDescriptors). 4. Double-click it, set the Base to Decimal, assign the numerical buffer value, and click OK.

Step 5: Apply the Changes

Registry modifications to network adapters do not take effect immediately. Apply the changes by doing either of the following: