Oh boy, here we go again.
At first, I will state, that BDO is running resplendently on both of my machines (PC with Win 7, and Laptop with Win 8). I've never met more stable application. Only disconnects are when I change characters (due to security reasons you might need to authenticate at the launcher again), or when there is maintenance. I had no issues staying logged into single character for 40+ hours. Other apps (like other-MMO-that-shall-not-be-nAAmed) were real pain. So let's dive in:
Connect your PC with Ethernet cable, if you are using WIFI stop reading this comment, as I cannot help you. If you will insist that WIFI is immaculate and does not cause any problems, I will promptly jump off the bridge. I can show you an experiment you can perform at home, where using a teaspoon can interrupt your WIFI connection. Human body is superb at breaking WIFI signal too.
If you are cabled, proceed to the next step.
Don't forget to create backup your System before doing ANY changes. Try to update your drivers, it might not hurt, and it's pretty straight forward. If issue persists, follow up to the next step.
If it's releated to Software issue, you have to install and READ THE FUCKING MANUAL of "WhoCrashed" http://download.cnet.com/WhoCrashed/3000-2094_4-75205821.html This app is the first hurdle you need to pass to understand what is happening in your PC.
Second step: If you are running Win 7 or never try:
If CPU and GPU are constantly running high, you might want to use MSI Afterburner to investigate further: http://www.softpedia.com/get/Tweak/Video-Tweak/MSI-Afterburner.shtml You don't need MSI hardware to use their application.
If it's related to HDD (the activity on HDD graphs is nearing 100%) you might want to use Samsung Magician to benchmark the health condition of your Drives: http://www.samsung.com/global/business/semiconductor/minisite/SSD/global/html/support/downloads.html You don't need Samsung hardware to use their application.
If any reports from WhoCrashed indicate memory errors/driver errors/cache errors, you should try to test your RAM with Memtest86+ http://www.memtest.org/ (burn it on CD and reboot PC).
Comparing your issue to other users will not help you solving errors. This idea is also valid for comparing RNG of other players to your own. Do not do this because that's how Urban Myths are being spread.
From my personal experience, first common element of the PC that usually fails are poor Network connection, second are Outdated Drivers. Third is HDD (Due to their mechanical parts that are wearing out), and last is RAM. Other issues are less common.
TL;DR: Please fill in the following table:
| Component | Checked | Shows no errors? |
|---|---|---|
| Network Activity | ||
| Drivers Updated | ||
| WhoCrashed | ||
| CPU Activity | ||
| GPU Activity | ||
| HDD Activity | ||
| RAM Activity |