For future reference, before purchasing hardware that you cannot physically see always research the product, reading customer feedback provided by retailers such as Newegg is invaluable;
http://www.newegg.co...D=11syr9fek9oed
Hindsight is a wonderful thing I know but had you read through the feedback at Newegg there is a strong possibility that you may have not purchased either item.
Options, consider swapping the adapter for a wireless USB type
http://www.newegg.co...N82E16833704045 GFX card
http://www.newegg.co...N82E16814121444 again take the time to read the feedback, look at the images available and you will see the low profile bracket provided.
NB: I do not mean to add to your woes but you must ensure that before you add any new hardware that your PSU (power supply unit) can provide enough clean, stable and uninterrupted power to all components, many GFX cards are demanding power wise so check what the card requires before purchasing as you may find that the present Bestec PSU is inadequate.
For guidance
http://www.10stripe....d/psu/brand.php