Hi,
I have the same problem with an “old” computer i7-7200, motherboard GA.Z77-D3H, DDR3 16GB and GTX 960. I have tried to change the GPU for a 1070i and the same result, numerous groups the fps fall to 30- 40. Changin resolution to 720 and the same behavior, it’s not a GPU problem.
I have overclocking the CPU from 3,6GHz to 4,8GH and I do not perceive change in fps
I forgot to comment that when the fps fall, the GPU remains at 50% and the CPU at 15%, which is similar to > 75fps.
Greetings
Thank you guys for your own experiences.
I’m coming to the conclusion now we can’t do much on our side.
Even the latest ultimate gamer PC running an i9 and huge RTX card will suffer of the same issue in large groups.
I’m thinking more and more about a network limitation.
I don’t know precisely what kind of data is sent my zwift servers. I just know they are using UDP protocol as it’s faster (but less reliable).
I guess they have to collect Power,HR and position etc… from all riders and then broadcast you the position and data of the others around you multiple time per second.
I assume the math is done on our local CPU and it has to wait for the necessary information and only then it can render your new position relatively to the others.
I will change my Internet Provider this month and I will have an increase in bandwidth (from 75mbps to 125mbps). But the data flow doesn’t really matter. It’s more the speed. I’ll try to measure my ping time before & after.
It there anyone who knows zwift server IP address ?
I’ve found one in my log file but it doesn’t answer.
Maybe they disabled the ping answering, to avoid any attack of this kind ?
Stéphane
I played Zwift last season with a ADSL 16/2.4 connection.
This season with a VDSL 100/40 connection.
Same PC.
No difference at all.
I guess a larger bandwidth doesn’t always mean a better ping time. 
Yesterday evening I searched for my zwift ip server address.
I couldn’t find it in the log files, so I used a network interface packet recorder.
The tool is free, from Microsoft, it’s called "Microsoft Network Monitor 3.4)
We can see both TCP & UDP protocol are used by ZwiftApp.exe and 2 different IP.
I’ve found 52.33.234.101 as the source IP and performed a ping, Traceroute, and nslookup.
I’m in Brussels, Belgium
**Microsoft Windows [Version 10.0.16299.1625]**
**(c) 2017 Microsoft Corporation. All rights reserved.**
**C:\Users\slouve01>ping 52.33.234.101**
**Pinging 52.33.234.101 with 32 bytes of data:**
**Reply from 52.33.234.101: bytes=32 time=162ms TTL=225**
**Reply from 52.33.234.101: bytes=32 time=162ms TTL=225**
**Reply from 52.33.234.101: bytes=32 time=161ms TTL=225**
**Reply from 52.33.234.101: bytes=32 time=161ms TTL=225**
**Ping statistics for 52.33.234.101:**
** Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),**
**Approximate round trip times in milli-seconds:**
** Minimum = 161ms, Maximum = 162ms, Average = 161ms**
**C:\Users\slouve01>tracert -h 40 52.33.234.101**
**Tracing route to ec2-52-33-234-101.us-west-2.compute.amazonaws.com [52.33.234.101]**
**over a maximum of 40 hops:**
** 1 <1 ms <1 ms <1 ms lvnudss01_vlan240.emea.dci.corp [10.58.56.2]**
** 2 <1 ms <1 ms <1 ms lvncors01-41.emea.dci.corp [10.56.0.41]**
** 3 2 ms 1 ms 1 ms lvnids02_g010.emea.dci.corp [10.56.0.106]**
** 4 1 ms 1 ms 1 ms 162.107.197.59**
** 5 2 ms 1 ms 1 ms dd5e002e9.access.telenet.be [213.224.2.233]**
** 6 * * * Request timed out.**
** 7 * * * Request timed out.**
** 8 * * * Request timed out.**
** 9 5 ms 5 ms 5 ms be-zav01a-rb1-ae-19-0.aorta.net [213.46.162.1]**
** 10 6 ms 6 ms 6 ms 213.46.162.5**
** 11 160 ms 150 ms 150 ms prs-bb4-link.telia.net [62.115.117.54]**
** 12 95 ms 94 ms 94 ms ash-bb3-link.telia.net [62.115.122.159]**
** 13 148 ms 147 ms 148 ms las-b24-link.telia.net [62.115.114.86]**
** 14 148 ms 148 ms 148 ms a100-ic-325183-las-b24.c.telia.net [62.115.155.111]**
** 15 * * * Request timed out.**
** 16 * * * Request timed out.**
** 17 * * * Request timed out.**
** 18 * * * Request timed out.**
** 19 154 ms 154 ms 154 ms 54.239.44.24**
** 20 * * * Request timed out.**
** 21 154 ms 154 ms 153 ms 52.93.15.48**
** 22 162 ms 166 ms 162 ms 52.93.15.29**
** 23 155 ms 154 ms 155 ms 52.93.14.176**
** 24 162 ms 161 ms 162 ms 52.93.246.185**
** 25 155 ms 155 ms 155 ms 52.93.246.87**
** 26 * * * Request timed out.**
** 27 * * * Request timed out.**
** 28 * * * Request timed out.**
** 29 * * * Request timed out.**
** 30 * * * Request timed out.**
** 31 161 ms 161 ms 161 ms ec2-52-33-234-101.us-west-2.compute.amazonaws.com [52.33.234.101]**
**Trace complete.**
**C:\Users\slouve01>ping 52.33.234.101**
**Pinging 52.33.234.101 with 32 bytes of data:**
**Reply from 52.33.234.101: bytes=32 time=162ms TTL=225**
**Reply from 52.33.234.101: bytes=32 time=161ms TTL=225**
**Reply from 52.33.234.101: bytes=32 time=162ms TTL=225**
**Reply from 52.33.234.101: bytes=32 time=162ms TTL=225**
**Ping statistics for 52.33.234.101:**
** Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),**
**Approximate round trip times in milli-seconds:**
** Minimum = 161ms, Maximum = 162ms, Average = 161ms**
**C:\Users\slouve01>nslookup 52.33.234.101**
**Server: localhost**
**Address: 127.0.0.1**
**Name: ec2-52-33-234-101.us-west-2.compute.amazonaws.com**
**Address: 52.33.234.101**
**C:\Users\slouve01>**
Impact of the ping for gamers :
Hi,
Curious, we have performed the same latency tests.
And the same result, it seems Zwift has servers in Amazon from California. With this website you easily get the latency of Amazon servers (AWS):
In Spain it gives me a latency of 180ms.
Greetings
Hi everyone,
GP Lama just upgrade his computer.
I told him about the network bottle neck.
I’m sure he’s going to have a look into it 