Depends on the motherboard. If you go to the in-depth review sites, like overclockers.com, they often include "box shots" or "unpacking shots" that show you exactly what comes with the mobo. I'd look around on Google for that kind of review of your mobo, and use it to guide my scavenging efforts, if I were you...
PS: sometimes the vendor site will tell you what comes with the mobo on the product page, too. If the other suggestions don't pan out, try that, too.
Computer Type PC/Desktop System Manufacturer/Model Number Homebrew OS Windows 10 CPU i7 6700 Motherboard Asrock Z170 Extreme7+ Memory 32 GB DDR4 2133 Graphics Card GeForce 750Ti Sound Card Asus Xonar DC Monitor(s) Displays 2xDell 2709 UltraSharp Screen Resolution 1980x1200
Keyboard MS Comfort Curve 4000 Mouse Logitech M325 PSU Corsair 850 Platinum Case Rosewill BlackHawk Ultra Cooling Dynatron K985 Ball Cooler Hard Drives Primary: Samsung 500 GB NVMe 950
2xRAID Cards with 2X250 GB Samsung mSATA SSD
Various other SSDs & HDs Internet Speed 300 Mbps Browser All of 'em Antivirus Norton Other Info January 2016 build
Unless it's some really rich MB, it won't come with much. Mandatory backside plate for outputs and couple of SATA cables. If it has video output, some kind of adapter DVI/HDMI/VGA is usually included too.
Computer Type PC/Desktop System Manufacturer/Model Number Home grown, home schooled. OS All kinds CPU AMD FX 6350 Be @4.7 GHz Motherboard GA-990XA-UD3 (rev. 1.1) Memory Kingston HyperX DDR3 1866 MHz Graphics Card MSI AMD R7 260 oc Sound Card Realtec 888 onboard Monitor(s) Displays 24" and 22" Screen Resolution 1920 x 1080
PSU Sharkoon, Silent Storm 660W Case Chieftec Dragon Full tower Hard Drives Kingston V300, 120GB
Silicon Power Velox 70- 240GB
WD 750 GB Green
WD 350 GB Green Internet Speed 15/3 Mbps Browser Firefox Antivirus WD, MBAM
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