Just wanted to be clear on when crashes occur.
Two errors are 0x8E and these are almost always caused by hardware and are particularly a strong indicator of corrupted memory, However, sometimes they can be caused by drivers.
In your case both cited the Nvidia display driver nv4_disp.dll as your probable cause for your system crashes.
The third error is 0xBE: ATTEMPTED_WRITE_TO_READONLY_MEMORY
A driver attempted to write to read-only memory. Commonly occurs after installing a faulty device driver, system service, or firmware. If a driver file is named in the error message, try to correct the problem by disabling, removing, or rolling back the driver.
Again the driver nv4_disp.dll was cited as probable cause.
First, update your Nvidia drivers. Use something like Driver Sweeper or Driver Cleaner Pro (there are free versions of both) after you uninstall, then reboot and install the latest drivers.
Second, and this is only a suggestion, with your Sli set-up you may want to consider updating your BIOS and/or chipset drivers.
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