If you take my advice you will uninstall it and leave it that way No, I do understand some people like these free toy programs but to my way of thinking there are always better alternative ways of doing the same thing. Often as you have found out they come at a price.
I find EasyTune6 useful and have never had a problem with it. I read about Smart6 and decided I'd be smart and not install it. From Gigabyte's description it sounds as if it interacts with (changes somehow) the BIOS. If I were have problems with BSOD's, I'd surely get rid of it. I had (have?) enough without it! From Gigabyte:
BIOS QuickBoot : Shorten boot up POST time !!!
There is nothing more frustrating than having to wait ages for your PC to boot.That is why GIGABYTE developed Smart Quickboot. Smart Quickboot speeds up the system boot-up process and shortens time it takes to enter the operating system. This is done in two ways. Part one is a BIOS QuickBoot. Normally, every time you boot up your PC, your BIOS checks your hardware to make sure everything is working properly. This takes time, as your system checks the memory, hard drives, etc. By enabling Smart QuickBoot, your BIOS will only run through the hardware scan once. If all your hardware checks out ok, the next time you boot, your PC will only scan the most critical components. This allows for a time saving of up to 3-5 seconds on the BIOS boot time alone.
The second part of Smart QuickBoot is OS QuickBoot. This utility allows you to power down your PC into a combination of Suspend Mode (S3) and Hibernate Mode (S4). By putting your PC into S3 and S4 mode is like putting your PC to sleep, allowing you to maintain your data, while at the same time, saving energy. When you power your PC back on, Smart QuickBoot will resume from Suspend Mode in a matter of seconds, rather than the time it takes to boot the OS. The great thing about OS QuickBoot is that your data is stored in both the memory thanks to the S3 state as well as being stored on your hard drive for the even deeper S4 state. This means that even if your PC is unplugged or you lose power, the next time when you boot your PC, it will resume from S4 automatically, using the data that was stored on the hard drive.