I have 5 Win10 systems using Avast Premium. Comcast 1.2 Gbps connection. I get 940 Mbps (practical maximum) on my 4 desktops, but my Dell laptop gets 50 - 150 Mbps (1Gbps wired connection) to the Internet. It is a fast system. With Avast uninstalled from the laptop, it gets the same 940 Mbps as the others. With Avast installed, it gets 940 Gbps on the local network, but the Internet is very slow. Have tried disabling every feature on Avast, and still poor until I completely uninstall. This has to do with leaving the local network and hitting the Internet. Tried tests directly connected to cable modem with same result.
Hi,
Since you have an Avast Ultimate subscription, can you please clarify:
- On the device that does not have the issue, which Avast applications do you have installed?
- On the device that has the issue, which Avast applications do you have installed?
- On the device that has the issue, after uninstalling which Avast application(s) did you notice the improvement?
- All systems have Full Premium, except Mail Shield and Real Site, with SecureLine VPN. I have never logged in to VPN on any of my machines. I don’t have Cleanup nor Tracker installed anywhere - they were VERY problematic.
- I just fully uninstalled all Avast from the laptop, ran Ookla SpeedTest app, got 940+ Gbps download. Installed Avast minimum configuration - File, Behavior, Web. SpeedTest numbers ranged from 117 to 816, mostly at the lower end. Uninstalled and again verified 940+. Installed Avast File Shield only. SpeedTest numbers were just as bad. Also, I verified this is a real slowdown by comparing some huge ordinary web downloads using different machines.
- Only true improvement comes from complete uninstall.
All this makes me suspect something in your core files for even minimal installs interacts with web access (not lan access, though). Could it be because the laptop has both wired and wireless connections, even though the wired connection is the only one active? Another difference I didn’t initially mention is the laptop is an i7, with Intel chipsets. My other computers are all AMD. However, all network adapters are Realtek. The laptop has a USB adapter, but I tried it on other machines, and they are still fast. Could it be some silly Dell software that I can’t diagnose? I removed that stupid SmartByte app long ago… I tried setting the laptop to fixed IP address with no change. Could this be an IPv6 issue? I have never bothered to learn anything about IPv6, but I see addresses reported when I run ipconfig.exe.
I answered my own question about IPv6 being an issue. I disabled IPv6, installed just File Shield, and I got the same poor Internet speed. So, I’m dismissing IPv6 as a possible issue.
Hi,
Can you please provide us with a performance recording? https://support.avast.com/article/Antivirus-Performance-recording-FAQ/
And if possible capture and send us a log from WireShark (this will help a lot):
- Download and install WireShark.https://www.wireshark.org/download.html
- Open WireShark and select your current network adapter ( “Wi-Fi” or “Ethernet” - see picture below):
- Click the blue “Shark” icon in the top-left corner of the window to start capturing the logs.
- Reproduce the issue.
- Once done, switch back to WireShark and click the red “Stop” button.
- Click File - Save to save the capture file to your Desktop or some other preferred folder.
- Send the file to us.
Very Interesting! I installed WireShark without Avast installed. I ran SpeedTest and got my full 940+. I then installed Avast minimum configuration, and ran WireShark without having Avast recording, 3 times. Each time produced 700+ with SpeedTest. Without running WireShark capture, I ran SpeedTest 6 times - 158,142,67,70,174,91. After that, I enabled WireShark capture and speed was back up to 700+. I ran Avast recording without WireShark capture, but it cuts off before SpeedTest completes. In this case I got the slow speed again. Sorry, but my WireShark logs are well over 1000 times your limit.