External temperature monitor - question

A friend of mine of thinking of getting one of those fan controller/temp monitor thingies that fits in to a front 5.25" bay in the tower, somthine similar to this item from Scythe. The question is: how/where is the best method/location for the CPU temp sensor? Ideally, it would be sandwiched between the top of the CPU and the base of the CPU cooler, but from what I've seen, these sensors are thick enough to where doing this would cause a serious (if not near-fatal) problem with the effectiveness of the CPU cooler because contact between the CPU cooler's base and the top of the CPU would no longer be perfectly flat and level; there would be this "lump" about the size of toothpick (a bit smaller I think, but you get the idea) in the middle. The same question would apply to the placement of the temp sensor for the GPU also....

Thanks!

 

I agree with your assessment and have avoided those type monitors for the same reasons. The most efficient heat transfer occurs ONLY with maximum direct surface to surface contact between the two mating surfaces. Sticking a log under the corner is not going to help with that, nor will even the best TIM (thermal interface materials) compensate as its duty is to fill the "microscopic" imperfections (pits and valleys), and not gaps caused by something foreign jammed in between.

Now that is not to say these controllers cannot be useful. They can. The sensor can be placed between the fins, for example, and used to monitor and control speed that way - but the temperatures would not be accurate, but they should be consistently off.

Since just about every CPU includes an internal sensor that can be monitored via the BIOS and software, I would stick to that. And if temperatures are still a concern, it is time to re-evaluate your case's cooling capabilities.

I commend anyone who is concerned about controlling heat - I wish everyone was. And if this is the only option, then I guess it will have to do.

 

Thanks for your response. The CPU does have a 'built in' thermal sensor, and it works fine and appears to be accurate. The dude that's buying the fan controller/thermal monitor just wants everything with this device to be totally functional and accurate. I already told him that the CPU sensor might be better used as a temp sensor for a hard drive, or the memory, where it can be mounted properly. I have used these sensors on CPUs in the past by stuffing the sensor way down in to the CPU cooler's fins to get as close to "ground zero" as possible and noticed a consistent temp difference of about 8c (if I'm remembering correctly; this was waaaay back in the AthlonXP socket462/A days) so it was easy to gauge what was going on. However, my friend who wants the controller/monitor does NOT want it to be 8c (or whatever) off of the actual temp whether it's consistent or not, but I think he's going to have to live with it, and I've already explained this to him. Now that I have a 2nd opinion which corroborates mine, I think he'll see the "light". Thanks again!

 

I want to win the lottery too.

Functional he can get. Consistency he can get. Accuracy he's not going to get - not with a little 2 cent diode sensor. If he wants accuracy, he needs a laser or infrared probe - but even those are accurate to +/- 2% or about +/- 2°C.

His best bet is to stick with the monitoring program that came on the utilities disk with his motherboard, or he can download it from the motherboard maker's website. Alternatively, he can use a 3rd party program (see below). These read the CPU's internal sensor - the critical area where no external probe can reach.
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I would keep an eye on your temperatures, particularly, the CPU temps. Your motherboard utilities disk should have a monitoring program (or check for a more recent version on your motherboard or PC maker's website). If none, I recommend CoreTemp for newer Intel and AMD64 CPUs. SpeedFan is a great and popular alternative, or you can try Motherboard Monitor. Unfortunately, I have found that these programs often have problems properly identifying and labeling the sensor they are reading. The temperatures shown are as accurate as the inexpensive, low-tech sensors will allow, but it may say System Fan instead of CPU Fan. Fortunately, the programs do allow you to edit the labels, so I use Everest to verify the temperatures (as it is able to put sensor to label correctly), then edit the label in the monitoring program. In Everest, look under Computer > Sensor, then wait a couple seconds for the readings to appear. Unfortunately, Everest does not minimize to the system tray to show real-time temperatures, otherwise, you could use Everest instead of the others.​

 

Thanks again . . . . I'm already very familiar with the apps metioned (CoreTemp, SpeedFan, Everest, etc), and since we're discussing it, my personal favorite is HWmonitor. I've found it to be consistent, accurate, and easier to interpret than SpeedFan (and more accurate than SpeedFan also even though both apps probably read the same sensors on the MB/CPU), and it supplies MUCH more info than CoreTemp, but CoreTemp is GREAT at what it does.... also, part of his reason for wanting the temp monitor/fan controller is for the "geek/mod/coolness" factor of having a glowing LCD readout panel in one of the drive bays.
LOL roflmao