MSI X58 motherboards are NOTORIOUS for hot IOH temps.
The rest of your PC could be a ****ing
igloo, and your IOH can be running at 60C or higher!!!
Unfortunately, it's a design flaw on MSI's part.
You have a few options for addressing the issue in order from least to most amount of work involved:
1) Put a small fan on the IOH heat sink. It might not help all that much, but it's minimal work to do so.
2) Remove the spring-loaded bolts off of the IOH heat sink and use something better to tighten it down so the heat sink has better contact.
3) Remove the IOH heat sink, clean off the thermal crap MSI used and use something better like some flavor of Arctic Silver instead.
4) Remove the IOH heat sink and use a third-party cooling solution like the Thermalright HR-05 IFX. Don't use the HR-05 SLI/IFX for the IOH--the fins will get in the way of your CPU's heat sink, the video card, or whatever you may have in the first PCI-e x1 slot.
For your Southbridge, you could either mount the existing heat pipe solution upside down and turn the unmounted IOH heat sink 90 degrees out of the way or you can use a Thermalright HR-05 IFX or SLI/IFX (probably the SLI/IFX because the video card will most likely get in the way of the regular IFX.
Thermalright HR-05 IFX:
http://www.thermalright.com/new_a_page/product_page/chipset/hr05_ifx/product_chitset_cooler_hr05_ifx.htmThermalright HR-05 SLI/IFX:
http://www.thermalright.com/new_a_page/product_page/chipset/hr05_sli_ifx/product_chitset_cooler_hr05_sli_ifx.htmIn any case, I normally like MSI products, but they screwed up with the X58 Pro boards. I'm already RMAing mine now...