While previous boards had troubles in matching exact clocks, both our today's motherboards clock nearly exactly at 200MHz. We tested the new boards with the latest Phenom II X6 processor.
Both boards feature 128MB DDR3 sideport memory clocked at 667MHz; this is what GPU-Z reports when the IGP is idle:
Unfortunately, our Phenom 1090T managed to scrap MSI's board in our overclocking tests. After receiving a new board we tried without pushing too much voltage, but the result was the same. Luckely we tested before with the 1055T. We reached 3.85GHz with both boards, at 1.4375VCore. We didn't like the fact that MSI's board lacks some overclocking features inside the BIOS but MSI told us "it's not designed to be a high-end board", meaning we won't see such features. The ASRock board does have all features, but lacks the possibility the see SPD values in the memory configuration. The board only remembers the last settings.
Of course both boards support overclocking of the IGP, but the performance is still below anything you would consider playable framerates for quite new games. So we think it's quite useless to do so.
Both boards support undervoltaging of the VCore, memory and IGP. Both boards had no trouble running Phenom II X6 1055T with 1.1750V. Please note that CPUz and Everest report about 1.2160V. So, it seems like X6s CPUs are getting more than they're requesting. Before you consider a system stable, run it about 48h with Prime95. Due to time-constraints we did it only for about eight hours.