Hello, I have a 7870 joker edition OC'd to 1250MHz/1650MHz but the problem is that it fluctuates constantly between 1250 and its stock 925. This is a problem because there is artifacting, a lot of it, and it becomes very unstable, however whenever I rarely get it to run at 1250/1650 constantly it doesn't go above 68-70degrees and it works fine for hours on end. But when I get it to work and then restart my computer I have to *** with MSI and CCC to get it to run at 100% speed again, what's the problem here?