Did you pop the VRM/ NB/ SB Heat sink off anf replace the TIM? Itactually kind of easy and if you're going to be pulling that SHtuff apart anyhow to check the PCIe sockets again, possibly, then I would definitely do it. Just take care to make sure that you don't tweak the HS and Pipes any. It won't sit on there correctly unless you striaghten it.
I used a HARD mounted mirror. One that doesn't flex at all. Place the whole heat sink against the mirror virtically, placing most of the preasure on the VRM/ NB chipset section of the heatsink, being that it's the heaviest. Then look to see if Both of the SB Screw holes are sitting about .5 of a MM away fromt he mirror surface. THAT is wat you want. That way you know that each of the Chips heat sinks will be perfectly sitting against the Chip surfaces.
Note though... Make sure that the SB and NB. VRM heat sinks are perfectly parralell. If not you will til get and uneven contact between the chips and heat sinks.... I used AS5. Then TX-3, Now back to AS5.... TX-3 didn't seem to do the job as well s they predicted....
Other than that, I use the Fan off of the stock PhenomII HS and mount it with a couple of screws over the NB HS.... Unless you want to water cool it! That's really all that you can do!
I actually did replace the NB with fresh TIM around the time i had the soda spill so it should be fine and i have had excellent temps before now...i didn't expect this much heat dump from the 4890/4870 combo but damn its ridiculous
The NB temp increase looks to mainly be caused by the added heat dumping from my 4870 as its right below the NB and the rear of my 4870 can and will burn you
I just checked and the NB is now sitting around 61C-63C after adding the fans...i have kept the stress testing going so the NB's not even had time to cool down
Everything looks to be under control at this point