For the past couple of weeks, Steam downloads have become extremely slow and unreliable. Downloads may sit at 0% for several minutes, then fluctuate anywhere from a few hundred KB/s to hundreds of Mb/s before dropping again. Games can also remain stuck at 99% for around 10 minutes, and Steam Cloud syncs sometimes fail.
My system has a Ryzen 9 7900X, RTX 5080, 32GB of RAM, and several WD Black NVMe SSDs, including a 4TB drive with about 2TB free. Temperatures and usage do not indicate overheating or throttling. I have a 1000/1000 Frontier connection; wired speed tests show roughly 700–750 Mbps download and 850–950 Mbps upload. Other launchers download at full speed, so the issue appears limited to Steam.
I have already tried both wired and wireless connections, changing Steam download regions, clearing the download cache, reinstalling Steam, using other SSDs, disabling write caching, restarting the router and PC, disabling the firewall and antivirus, changing DNS servers, disabling HTTP/2, and running several Windows network reset commands. There are no Steam download limits configured. What else could explain the inconsistent speeds and long pauses near the beginning and end of downloads?
3 Answers
Try setting a very high Steam download limit instead of leaving it unlimited—for example, 1,000,000 Kbps. It sounds counterintuitive, but this fixed a similar issue for me when Steam was behaving unpredictably.
Keep an eye on Steam's disk-usage graph while the network speed drops. Steam may pause network activity while unpacking, decrypting, or verifying files, which can also explain the long wait at 99%. It may be worth repairing the Steam library through Steam's Storage settings, temporarily excluding the library folder from antivirus scanning, and testing with IPv6 disabled. Since disabling HTTP/2 helped briefly and Cloud sync is also failing, this could be a Steam client or routing problem rather than a hardware or bandwidth issue.
Do you have more than one Steam library, and does this happen only with updates or also with fresh game installations? Comparing a clean reinstall of one game against an update can help determine whether file patching is involved.
I have multiple libraries on different drives, and the behavior is the same across all of them. It happens with both new downloads and updates.
The disk usage drops along with the download speed rather than continuing independently, so it does not seem like the SSD is simply catching up. I already disabled Defender and other antivirus protection completely, but I can still try a specific library exclusion. My libraries are newly installed across multiple drives, and the problem affects all of them. I will also test repairing the library and disabling IPv6.