Just updating with new info!
I've tried many different frequencies for this miner. It ran just fine for 3 days at 600, so I decided to test higher ones. I tested from 7500 all the way down to 650. One of the boards in it just wouldn't function at anything above 675. At 675, I ran it for about an hour and one of the boards decided to stop functioning. I tested it again at 668, it ran for about 3-4 hours and then the same thing happened. There's no permanent damage at all, it's like the board's individual components differ so that the other two are great and one is below average. Ideally you want all three boards to run, so I turned it down to frequency 662, and so far it's running fine.
average sols
675 = 15.00 ksol
668 = 14.90 ksol
662 = 14.75 ksol
Everything seems to be going well so far, I will keep this updated with any further information so someone else can benefit from this in the future. I plan on moving the miner itself into a colder room of the house as well, and I can see if that changes the results as well. Still though, I'd appreciate anyone who knows more than me about this to give me any advice! I am a novice when it comes to this.