Network quality drops during game downloads?

Your game starts lagging as soon as a large patch begins downloading. Other devices may also feel slow, or your ping may rise even though the download speed looks high. The cause could be a busy connection, weak Wi-Fi, or a problem elsewhere on the route to the game server.

The Bufferbloat Test checks how much your connection's delay grows while data is downloading or uploading. Use it to see whether a loaded connection is likely to make gaming feel less responsive, then compare that result with what happens during an actual patch download.

Test your connection during load

1. Pause game downloads, cloud backups, video streams, and other large transfers. Connect your computer to the network you normally use for gaming.
2. Open the Bufferbloat Test and run it while the connection is otherwise quiet. It measures how delay changes under download and upload load, and gives a grade from A+ to F.
3. Note the grade and whether delay rises more during downloading or uploading. A strong increase under load can make online play feel sluggish even when the connection is fast.
4. Close the test, start a game patch, and check the ping or latency display in your game, if it has one. Compare it with the same game when the patch is paused.
5. Pause the patch briefly and see whether the in-game delay falls. Repeat the comparison once if the result is unclear, keeping other network activity as similar as possible.

Do not run the Bufferbloat Test at the same time as the patch download when you are trying to isolate the patch's effect. The test creates its own download and upload load, so running both together can make the connection busier than the game download alone.

What the result means

The Bufferbloat Test grade is low and delay rises under load

Your connection's response time gets worse when it is busy. A download can fill a queue in your router or modem, leaving game traffic waiting behind other data. This is a likely reason for lag during large transfers, but it does not prove that every game server or patch download will behave the same way.

The test looks good, but the game still lags during a patch

The issue may be specific to the game's download server, your Wi-Fi signal, or another device using the network. The Bufferbloat Test measures the route between your browser and its test server, not the route to the game server. Compare the in-game ping with the patch paused, and try a wired connection if possible.

The game lags even when the patch is paused

The download may not be the cause. Check whether other devices are streaming, backing up files, or downloading updates. If the connection still has problems when it is quiet, test its stability separately with Connection Stability, which checks response time, jitter, lost requests, and dropouts over a few minutes.

The download is fast, but actions feel delayed

Download speed and responsiveness are different measures. Speed describes how much data arrives over time. Latency is how long a small request takes to get a response. A connection can deliver a patch quickly while still having a long wait for game inputs to reach the server and return.

How to reduce lag during game downloads

1. Limit the game's download speed. If your launcher offers a download limit, set it lower and test the game again. In Steam, look in Steam › Settings › Downloads for the download speed limit. Leave some capacity for game traffic instead of letting the patch use all available bandwidth.
2. Pause other large transfers. Stop cloud backups, file syncing, video streams, and downloads on other devices while you play. Ask other people on the network before interrupting their activity.
3. Use Ethernet if you can. A wired connection avoids Wi-Fi interference and weak signal problems. If you must use Wi-Fi, move closer to the router and test with fewer walls or closed doors between the device and router.
4. Check whether the problem follows Wi-Fi. On Windows 11, open Settings › Network & internet › Wi-Fi and confirm which network you are using. On a Mac, open System Settings › Network › Wi-Fi. Compare the game with a wired connection or another Wi-Fi band if your router offers one.
5. Check for background updates. On Windows 11, look under Settings › Windows Update for activity that may be downloading during play. On macOS, check System Settings › General › Software Update. Let necessary updates finish before a match, or pause nonessential transfers through the app that is downloading them.
6. Restart the router and modem. If lag continues after other transfers stop, unplug the router and modem, wait about 30 seconds, then reconnect them. Give the connection a few minutes to return before testing again.
7. Check your router's traffic management options. Some routers offer Quality of Service (QoS) or Smart Queue Management (SQM), features that can prioritize time-sensitive traffic or manage queues. Names and controls vary by model. Follow the router maker's instructions, and compare results before and after changing one setting.

When the problem may be outside your home

If lag remains when the patch is paused, other devices are quiet, and a wired connection makes no difference, the cause may be your internet provider's route or the game server. Compare at another time and check whether other online services also respond slowly. A browser test can show how your connection behaves to its test server, but it cannot diagnose the path to a particular game server.

Keep the patch paused while you play if limiting its speed does not help. Resume it afterward, when the connection is no longer needed for a real-time match.