I am trying to find a hot spot and I need some direction Please

kahoona

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May 26, 2010
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Hi
I have a hot spot somewhere in my PC. Almost certainly on the MB. What started me wondering is a serious hot electronics smell that happened any time CPU use rose above idle. Watching a HD movie it is noticeable across the room. I fear damage. It also makes my eyes water. so far I have:
1- replaced my not so good power supply with an 850W Seventeam to see if it was the cause. No change.
2- got Speedfan 4.40 and spent a week calibrating it. I have found that my CPU,hard drives and cores are all well within tolerances as are the temp2 and temp 3 which I am thinking are the ambient and the remote ambient. I got this by comparing Bios readings with speedfan. Not certain though. Speedfan shows a Temp 4 that is very high. and that rises pretty fast with any CPU use and coincides with the burning smell. It does rise and fall with use and at one time it was getting above 70/80c. Since it changes I don't think that it is a false reading.
3- After 2 I cleaned the case carefully, removing the fans and really cleaning. I discovered that one of my case fans was in backwards (whoops) and fixed that. I did see an improvement.
4-I replaced all e case fans with new Noctua fans(wow they are unbelievably quiet!) and got some more improvement in the temp 4 reading.
This is where I am now.Temp 4 can go tp 65c at 100% CPU use. It is not associated with Video, it goes up regardless of weather I load it with Video or Antivirus scans. I am running a HD video now that uses 9% CPU and temp 4 is 53c but I suspect that the real hot spot is hotter than that because of the smell which I am getting now. Although my CPU fan changes speed according to load the other three seem to be oblivious to the heating. Performance is never affected. I have some improvement but I need more.
I need to
A- Find out where Temp 4 resides and therefore where the heat is so that if necessary I can direct air at that point and
B- Get all the cooling fans to run at speed when needed. Right now Fan2 (wich is plugged into the aux header does spool up. I have tried to get Speedfan set to increase the speed on more than one fan when temp 4 rises but I must be missing something!
Any suggestions would be appreciated on either fan speed or location. Sorry for the long post but I thought the info would be necessary.


Core 2 quad Q6600
D975XBX2 MB
3 80mm fans
5 SATA hd's
ATI 5700 card
4G ram


 

kahoona

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May 26, 2010
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Hi Salliello'
Thanks. Since the CPu is running cool even under 100% load then it is the Northbridge. That was running hotter than the rest of the MB according to my IR thermometer. I'll spot cool it with a small fan or ice cube in plastic and verify that temp 4 changes. Opening the case and aiming a desk fan into it had helped a little in the beginning and that fits in. I do appreciate the help
Ollie UK,
Nice little device. I'll look for it and if I can't find it I can make a vinyl housing for another Noctua fan to fit. Those little fans are amazing quiet! Thanks for the link to the guide. I'll spend some time on that for sure.
I'll let you know what happens.
The more I learn about this stuff the more I realize how much I do not know!
Thanks
Kahoona
 

kahoona

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Thanks guys. You nailed it. I measured high 40's resting and as high as 87c with a high def on the big screen. More normally though I got in the 60's under 50% CPU. A medical chill pad on the North Bridge heat sink brought it down 20c fast so that is that. I stuck an old 80MM an inch away and it now runs 58 @ 75% cpu and 51 at 20% which is better but not quite enough. I'll get a nice quiet 40mm fan and install it right on top. If that is not enough I'll get a fancy cooler. What temp am I looking for anyway? I would kind of like to keep it under 50 at full use but is that reasonable?
 

kahoona

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Hi
Here's the report. I still have a problem. Bummer. I pulled the Northbridge heatsink and found (gasp) the dried up remnants of some thermal tape. Thanks Intell. I cleaned the stuff off and I put some Arctic Silver on the surfaces and reinstalled it. It is a good sized passive heat sink. I added a Noctua fan blowing down through it. I plugged the fan into the front mb socket. I went over the case to make sure I had the best possible airflow. I still get the same readings. The intel specs say that the Northbridge can go to 110c before being a problem. The only things that help are the generalized things like putting a room fan against the open case side or case cleaning. So now I have fixed a Northbridge problem that needed doing but I still have a hot electronics stink, burning eyes and a sneezing cat.
1-Since Temp 4 has not changed with the newly reseated and pasted heatsink and fan I suspect it might not be the NB. 2- My NB is now fine, thank you.
3- What is overheating and how can I find it before it fries for good or does permanent damage to the cat's breathing? Help please!
Kahoona
 

kahoona

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Thanks for the reply. I want to make sure I understand.I currently have the stock 2"x2"x 3" aluminum heat sink and a 80MM fan on the NB and it has not made any difference in the hot electronics smell or in the temp on Temp 4. Are you thinking that it needs a bigger heat sink still?
Kahoona
 

kahoona

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Hi
I installed a Silenx Extrema chipset cooler because could be attached to the loops provided by intel. I should mention that the stock mounting system on the Silenx does not give a solid contact with the NB but I was able to increase the stability and pressure with 4 heavy Zip Ties :-]. My Idle temp is 47c and it goes to 53c under load. Is that an OK NB temp? I still get the hot circuit smell with any load. Anybody else get this? Where should I check next? I can run memtest in 6 instances to max out the CPU and load the NB and SB without any problem but most other things cause the heating smell. I am stumped.