Hi,
I also have same problem as sparkettaccio and I see that both have Mac mini (Mid 2011). I also did clean install of Sierra High and problem still exist, I didn't install any app before checking. On my MacBook Pro there is no that problem.
Here is mine report:
EtreCheck version: 3.4.6 (460)
Report generated 2017-11-05 08:57:22
Download EtreCheck from https://etrecheck.com
Runtime: 2:27
Performance: Excellent
Click the [Lookup] links for more information from Apple Support Communities.
Click the [Details] links for more information about that line.
Problem: Other problem
Hardware Information:ⓘ
Mac mini (Mid 2011)
[Technical Specifications] - [User Guide] - [Warranty & Service]
Mac mini - model: Macmini5,1
1 2.3 GHz Intel Core i5 (i5-2415M) CPU: 2-core
8 GB RAM Upgradeable - [Instructions]
BANK 0/DIMM0
4 GB DDR3 1333 MHz ok
BANK 1/DIMM0
4 GB DDR3 1333 MHz ok
Handoff/Airdrop2: not supported
Wireless: en1: 802.11 a/b/g/n
Video Information:ⓘ
Intel HD Graphics 3000 - VRAM: 512 MB
2269WM 1920 x 1080 @ 60 Hz
Disk Information:ⓘ
KINGSTON SUV400S37480G disk0: (480.1 GB) (Solid State - TRIM: No)
[Show SMART report]
EFI (disk0s1 - MS-DOS FAT32) <not mounted> [EFI]: 210 MB
(disk0s2) <not mounted> [APFS Container]: 479.89 GB
USB Information:ⓘ
USB20Bus
hub_device
Apple Inc. BRCM20702 Hub
Apple Inc. Bluetooth USB Host Controller
USB20Bus
hub_device
Apple Computer, Inc. IR Receiver
Thunderbolt Information:ⓘ
Apple Inc. thunderbolt_bus
Virtual disks:ⓘ
Main (disk1s1 - APFS) / [Startup]: 479.89 GB (425.67 GB free)
Physical disk: disk0s2 479.89 GB (425.67 GB free)
(disk1s2) <not mounted> [Preboot]: 479.89 GB
Physical disk: disk0s2 479.89 GB
(disk1s3) <not mounted> [Recovery]: 479.89 GB
Physical disk: disk0s2 479.89 GB
(disk1s4) /private/var/vm [VM]: 479.89 GB
Physical disk: disk0s2 479.89 GB
System Software:ⓘ
macOS High Sierra 10.13.1 (17B48) - Time since boot: less than an hour
Gatekeeper:ⓘ
Mac App Store and identified developers
Startup Items:ⓘ
noip2: Path: /Library/StartupItems/noip2
Startup items no longer function in OS X Yosemite or later
System Launch Agents:ⓘ
[not loaded] 10 Apple tasks
[loaded] 182 Apple tasks
[running] 96 Apple tasks
System Launch Daemons:ⓘ
[not loaded] 37 Apple tasks
[loaded] 187 Apple tasks
[running] 105 Apple tasks
User Launch Agents:ⓘ
[loaded] com.google.keystone.agent.plist (Google, Inc. - installed 2017-11-04) [Lookup]
User Login Items:ⓘ
Spectacle Application
(/Applications/Spectacle.app)
Viber Application - Hidden
(/Applications/Viber.app)
iTunesHelper Application (Apple, Inc. - installed 2017-11-04)
(/Applications/iTunes.app/Contents/MacOS/iTunesHelper.app)
No-IP DUC Application - Hidden
(/Applications/No-IP DUC.app)
Backup and Sync from Google Application
(/Applications/Backup and Sync.app)
Internet Plug-ins:ⓘ
QuickTime Plugin: 7.7.3 (installed 2017-10-25)
Safari Extensions:ⓘ
[enabled] Adblock Plus - Eyeo GmbH - https://adblockplus.org/ (installed 2017-11-04)
[enabled] Harakirimail - Wahlberg Research & Development - https://harakirimail.com (installed 2017-11-04)
[enabled] Polyglot - Yasuaki Uechi - https://github.com/uetchy/Polyglot (installed 2017-11-04)
3rd Party Preference Panes:ⓘ
None
Time Machine:ⓘ
Time Machine not configured!
Top Processes by CPU:ⓘ
32% WindowServer
17% com.apple.WebKit.WebContent
12% com.apple.WebKit.Networking
7% Safari
4% nsurlstoraged
Top Processes by Memory:ⓘ
601 MB kernel_task
371 MB Safari
236 MB Backup and Sync
234 MB com.apple.WebKit.WebContent
204 MB com.apple.WebKit.WebContent
Top Processes by Network Use:ⓘ
Input Output Process name
7 KB 10 KB apsd
8 KB 6 KB mDNSResponder
7 KB 4 KB AddressBookSourceSync
3 KB 1 KB Viber
3 KB 802 B netbiosd
Top Processes by Energy Use:ⓘ
13.62 WindowServer
4.96 com.apple.WebKit.WebContent
3.32 com.apple.WebKit.Networking
2.04 hidd
Virtual Memory Information:ⓘ
3.91 GB Available RAM
2.10 GB Free RAM
4.09 GB Used RAM
1.81 GB Cached files
0 B Swap Used
Software installs (last 30 days):ⓘ
Python: (installed 2017-11-04)
Install information may not be complete.
Diagnostics Events (last 3 days for minor events):ⓘ
2017-11-04 11:45:48 Backup and Sync.app High CPU use [Open] [Details]