The answer is: Maybe
This is your board: Intel® Desktop Board DP45SG Product Specifications
It is already nine years old.
It has 2 PCIe x16 2.0 slots. The key here is they are PCIe Rev 2.0.
It seems the video card is from ~2014. I cannot determine if the GTX 750ti is a PCIe 2.0 or 3.0 card. You will need to determine this.
If it is 2.0, you have a better chance of it working, as the DP45SG supports 2.0. If the card is 3.0, then you have a lesser chance. Although the card will probably claim backward compatibility, this is often not the case.
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At this point, I suggest contacting your video card manufacturer; they might have a list of compatible motherboards with this graphics card; however, as Al Hill mentioned above this motherboard is old and the graphics card is newer and you could experience some compatibility problems.