It depends. I recommend that prior to your appearance in a South Carolina court that you correct the issue in Texas and obtain a valid SC driver's license. Law enforcement officers and court officials want people to have valid licenses and will work with you to make sure the mistake is corrected.
GA does have a super speeder law. Contact a GA lawyer for confirmation, but it is my understanding that if you are charged with speeding more than 85 mph on a highway you can be charged with additional fees. If you have a good driving record, a GA lawyer can usually work with the court to insure the charge has minimal affects on your SC driver's license. Make sure you contact a GA traffic attorney prior to your court date.