Hey everyone, 
I have a 790i ultra , with a  Xeon  and 8gb of Crucial BLS4G3D1609DS1S00 DDR3-1600 
(just mentioning the ram because the mb is supposed to support up to 4 gb, but i have tied up to 10gb with success.)
 
AAaanyway, i am trying to lower the spp and mcp temperatures, right now at 50c (SPP) and 56c (MCP).
I do know that those are my northbridge and soutbridge, but i am researching with an IR thermometer and i cant seem to find the actual hotpoint in order to set a fan near it.
Could someone please tell me where those temp sensors are located on the motherboard?
Here's a pic of the motherboard if anyone feels like drawing: 
 
Regards, 
k.

Welcome to the forums Krasatos.
 
Good question, and I don't exactly know..Tried to find a white paper about the NVIDIA chipset when I had my 790i FTW and no luck..I do remember reading somewhere that the max temp for the MCP and SPP chips is 90C..Mine was running at ~80C and ~65C respectively (using Everest Ultimate/AIDA64 Extreme).
 
If you don't have a chipset fan, you can strap a 3-wire 60mm x 60mm x 25mm fan on the Northbridge and plug it in the mobo MCP/SPP fan connector like many others have done..You can also manually set the nForce (chipset) Fan to 100% and adjust the MCP and SPP voltage in the BIOS..These would be the first things to do.  
 
I took off the vapor chamber chipset cooler on my FTW  (Ultra cooler in attachment) and replaced the TIM along with removing the foam padding around the chips (cicled in red) and filing down the standoffs and plastic feet (circled in green) by about .030in or so for a tighter fit..Also replaced the thermal pad (blue lines) for the MOSFETs..Mobo removal is req'd..This would be the most drastic thing to do..It helped a little, maybe 8C. 
 
The 790i chipset is known for running notoriously hot, especially on the FTW model, but with those temps you're seeing now, I would not sweat it in the least bit..They are good..If the chipset has original TIM, it's probably dried up garbage by now.

Hey Bob, Let me just clear out that i personally am not the geek and mastermind behind this upgrade.
I do have some past overclocking experience but a friend, who heard i had the 790i (and loves it for some reason :)) decided to upgrade it to me.
So he got one of those 771->775 xeon pre-cut processors and a used gtx770 and installed them for me (the 8gb ram i bought some time ago myself)
 
Anyway, since i have the "best silent pc" (where best silent pc means that i cut a hole in the wall and placed the tower in the room next door, so i can have the fans at 120% without caring too much) i have the task to keep an eye on the temperatures and report back to him for troubleshooting.
 
When i first got the board the nforce fan was not included in the box (for some reason) so i just screwed on a generic fan on that small heatsink under the cpu fans:


 
 
I also found an old asus "weird format" fan that i squeezed under the gpu and is blowing towards SB.
 

With those two installed i am getting the following readings on AIDA
 

and the following (different readings) are from hwmonitor
 

 
Fortunately it does not bother me that the tower sounds like a lawnmower... so there's that.
1. The two programs report totally different temperatures and fan speeds on every reading (if im not mistaken), what's up with that? which one do i trust?
2. Also, it seems like the AIDA (former EVEREST) reports the SPP and MCP temperatures but they are nowhere to be found on hwmonitor. 
3. If 49 and 54 celsius are cool enough on idle i dont think i will get into the trouble of removing everything, trimming the stand-offs and applying new paste as you said bob. i won't OC the computer further, for now.
 
edit:
4. i forgot the most important thingy, the actual reason why i looked into the temperatures. I have an infrared thermometer hanging around, so i thought why not test it... the temperatures i get (depicted below) are far lower than the ones reported... unless i am not targeting the correct spot on the mobo.
(tested it on my forehead too, just in case, it shows ~34, which i guess is ok)
 
 
Could the sensors be off? any ideas?
 
Just my thoughts and troubling.
Let me know what you think.
Regards. 
harry

The Ultra chipset was normally passively cooled, unlike the FTW and Digital that had a preinstalled fan..The Ultra chipset fan was optional/not preinstalled and should have been included as an accessory, but was known to be forgotten to be included on occasion..The fan is normally not neccessary if case ventilation is decent and you're not overclocking.
 
HWMonitor might not read certain sensors correctly or try to read a nonexistent sensor and make you guess which sensor is which..I always used Everest Ultimate (now AIDA64) which you can set up to log min/max/avg readings by going to File (top left of main screen) -> Preferences -> Logging -> Log to HTML log file..Are you using the Trial Version or did you pay for the Full Version?
 
What I would do is see what the min/max/avg chipset temps are in AIDA64 after about 10 minutes without those two little fans blowing on things..The IR thermometer is pretty much useless because it doesn't measure the actual chip temp under the heatsink..But like I said, the chipset TIM may pretty much be dried up garbage by now.