I have the same board and while certainly not a high-end enthusiast's board, not sure I would call it for the entry level user either. That is, I don't consider myself an entry-level overclocker. When I first got into OCing a couple decades ago, it involved studying schematics then moving and re-soldering jumpers on the motherboard! Frankly, I find the BIOS menu options to change voltages and timings a bit boring today. That's why I like the options provided by Gigabyte with this board. I can use the turbo mode to push my i7 3770 (not the k version) to 4.2GHz and keep my temps well below 60° with OEM cooler with no problems (though I have it down to 3.9Ghz to keep temps around 35°). But, I'm a old-timer electronics technician so my background is a bit different from most computer enthusiasts today. So if I want more speed, I prefer to just buy it.
I definitely would say Gigabyte did not mislead you about it's OC capabilities. I am afraid it is a matter of insufficient homework and research before buying. When researching motherboards, I tell folks to download the user manuals and see what the preset vs automatic vs manual options provided allow.
The fact is, this board does provide some decent OC options that provide a good balance in speed and stability, while keeping heat under control. Unfortunately you didn't tell us anything about your temps when pushing your system and that may be a big part of your stability issue. Did you buy a Retail boxed CPU that came with an OEM cooler? If so, are you using the stock OEM cooler on the CPU, or did you void the warranty
(yes, that's a fact) by using an aftermarket cooler? Or did you buy an OEM CPU that did not come with an OEM cooler? In either case, what cooler are you using and did you ensure a proper layer of TIM (thermal interface material)? Please note the last line in my sig.
I do agree with Wrench concerning your choice of CPU. It is a great CPU - no doubt! But as noted through his link and here
heat management with extreme OCing can be an issue.