These sensors are basically a resistor like the NTC resistor used in washing machines, the resistance changes depending on the temperature. Here is an example

https://www.aliexpress.com/item/32448482595.html

dominusprog wrote on 2024-10-29, 20:27:

These sensors are basically a resistor like the NTC resistor used in washing machines, the resistance changes depending on the temperature. Here is an example

https://www.aliexpress.com/item/32448482595.html

Thank you for the tip, is there a way to recover it? The ones you linked seem bigger than this one, do you think it would be possible to find anything similar?

Nemo1985 wrote on 2024-10-29, 20:30:

dominusprog wrote on 2024-10-29, 20:27:

These sensors are basically a resistor like the NTC resistor used in washing machines, the resistance changes depending on the temperature. Here is an example

https://www.aliexpress.com/item/32448482595.html

Thank you for the tip, is there a way to recover it? The ones you linked seem bigger than this one, do you think it would be possible to find anything similar?

https://www.ebay.com/itm/284425978285?_skw=Mo … ABk9SR4rbncnbZA

dominusprog wrote on 2024-10-30, 08:39:

Nemo1985 wrote on 2024-10-29, 20:30:

dominusprog wrote on 2024-10-29, 20:27:

These sensors are basically a resistor like the NTC resistor used in washing machines, the resistance changes depending on the temperature. Here is an example

https://www.aliexpress.com/item/32448482595.html

Thank you for the tip, is there a way to recover it? The ones you linked seem bigger than this one, do you think it would be possible to find anything similar?

https://www.ebay.com/itm/284425978285

That's it, thank you!
I just need to find if it's going to be sold in Europe too!
Apparently they don't, in the meanwhile I opened the front panel of the case, obviously the board is proprietary and the connector for the sensors is this one:

The question is, can I buy those sensors, cut the cables and connect the new sensor to the old cables?

So I bought two of those:
https://www.ebay.com/itm/264444563717
Any idea about how I should proceed when I get them? I'd love to be able to adapt the connector but I do not think I would be able to do it without instructions.
The alternative is to cut the cable of the old and new sensor then solder the two parts?

Nemo1985 wrote on 2024-10-31, 20:50:

So I bought two of those: https://www.ebay.com/itm/264444563717 Any idea about how I should proceed when I get them? I'd love t […]
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So I bought two of those:
https://www.ebay.com/itm/264444563717
Any idea about how I should proceed when I get them? I'd love to be able to adapt the connector but I do not think I would be able to do it without instructions.
The alternative is to cut the cable of the old and new sensor then solder the two parts?

Easy and non-permanent way (I'll explain why in a bit): cut the cable of the old sensor and solder two pins to the exposed wire that are the right size to go into the socket of the new sensor. Then attach new sensor to that.
Why?
-Because the new "sensor" (thermistor) might actually be incompatible.

There are two types of thermistors: NTC (negative temp. coefficient) and PTC (positive temp. coeff.).
NTC: resistance deceases with increasing temperature (inverse relationship).
PTC: resistance increases with increasing temperature (non-inverse relationship).

In addition to that, note that thermistors can have different "cold" resistance. The one you purchased is 10 kOhm... so that means probably 10 kOhm at room temperature (i.e. at 25 degrees Celsius.) Of course, without an actual part number (and thus no way to get a datasheet) for the component you purchased, there's really no way to know anything about the specs of the component. And thus, there's no guarantee that the new thermistor will actually measure the temperature accurately.

With that said, once you attach the new thermistor to the wires of the old one, you might want to test it out against some known temperatures. One easy way is to take one of the working sensors and put that along with the new sensor on a hot surface or part, but where there's not much air movement around. Then compare if the two sensor show the same temperature after about a minute of them sitting on that hot surface/component. Now put both sensors on a much cooler component or surface and see if they read the same temperature again (after waiting for a bit, of course.) If they do... then at least you know your new sensor is precise.

As for temperature accuracy (and this goes for all of the sensors in the case, not just your new one)... that will require a completely different test.
A known good and accurate way is to make some ice water and measure the temperature of that. It should show close to freezing (a degree or two above 0 Celsius.) Since these thermistors have current running through them, there's a chance your readings might get affected if they get wet, especially if you have hard water. For best results, it would be wise to make the ice water (both the water and the ice) out of distilled or deionized water so that it would be as little conductive as possible.

momaka wrote on 2024-11-01, 14:16:

Easy and non-permanent way (I'll explain why in a bit): cut the cable of the old sensor and solder two pins to the exposed wire […]
Show full quote

Easy and non-permanent way (I'll explain why in a bit): cut the cable of the old sensor and solder two pins to the exposed wire that are the right size to go into the socket of the new sensor. Then attach new sensor to that.
Why?
-Because the new "sensor" (thermistor) might actually be incompatible.

There are two types of thermistors: NTC (negative temp. coefficient) and PTC (positive temp. coeff.).
NTC: resistance deceases with increasing temperature (inverse relationship).
PTC: resistance increases with increasing temperature (non-inverse relationship).

In addition to that, note that thermistors can have different "cold" resistance. The one you purchased is 10 kOhm... so that means probably 10 kOhm at room temperature (i.e. at 25 degrees Celsius.) Of course, without an actual part number (and thus no way to get a datasheet) for the component you purchased, there's really no way to know anything about the specs of the component. And thus, there's no guarantee that the new thermistor will actually measure the temperature accurately.

With that said, once you attach the new thermistor to the wires of the old one, you might want to test it out against some known temperatures. One easy way is to take one of the working sensors and put that along with the new sensor on a hot surface or part, but where there's not much air movement around. Then compare if the two sensor show the same temperature after about a minute of them sitting on that hot surface/component. Now put both sensors on a much cooler component or surface and see if they read the same temperature again (after waiting for a bit, of course.) If they do... then at least you know your new sensor is precise.

As for temperature accuracy (and this goes for all of the sensors in the case, not just your new one)... that will require a completely different test.
A known good and accurate way is to make some ice water and measure the temperature of that. It should show close to freezing (a degree or two above 0 Celsius.) Since these thermistors have current running through them, there's a chance your readings might get affected if they get wet, especially if you have hard water. For best results, it would be wise to make the ice water (both the water and the ice) out of distilled or deionized water so that it would be as little conductive as possible.

Thank you for the complete answer.
About the tests you suggest I can surely do them. Since there are 2 other sensors (one is sys and placed on the case, the other is vga and it can be moved around it won't be difficult, they seem quite reasonable as numbers.
What I noticed with the broken sensor is that if I wet it and pinch on my fingers the temperature goes up (still lower than the real one).

So according to your suggestion I will need to cut the wire of the old sensor and use 2 male pins to connect to the new one? I didn't think about it but it's a good idea, but I need to source the 2 pins, any suggestion where to get them?
Thanks

Nemo1985 wrote on 2024-11-01, 15:59:

So according to your suggestion I will need to cut the wire of the old sensor and use 2 male pins to connect to the new one? I didn't think about it but it's a good idea, but I need to source the 2 pins, any suggestion where to get them?

Well, my first go-to place for parts is my scrap bin of non-working hardware. If you have any non-working motherboards or video cards or hard drives, chances are they'll have what you need. In particular, if you have any dead IDE drives, the pins from the IDE connector are the right fit for header pins.
I also use leftover component leads (typically cut leads from new capacitors that I've installed) quite often. These are usually a little smaller in diameter than proper header pins, but they can still be soldered onto wire ends and used as such. They just don't make as tight of a connection.
And if those are not options, perhaps just buy a random header from a parts distributor (online or local).
Last but not least... if the wires that go to the old sensor are thin enough (but not too thin), then you can simply strip them a bit and twist them, then coat evenly with solder. Then if needed, give them a bit of sanding and straightening to make them as close as possible to header pins. After that, you can just shove them into the connector of the new thermistor.

momaka wrote on 2024-11-04, 14:25:

Well, my first go-to place for parts is my scrap bin of non-working hardware. If you have any non-working motherboards or video […]
Show full quote

Nemo1985 wrote on 2024-11-01, 15:59:

So according to your suggestion I will need to cut the wire of the old sensor and use 2 male pins to connect to the new one? I didn't think about it but it's a good idea, but I need to source the 2 pins, any suggestion where to get them?

Well, my first go-to place for parts is my scrap bin of non-working hardware. If you have any non-working motherboards or video cards or hard drives, chances are they'll have what you need. In particular, if you have any dead IDE drives, the pins from the IDE connector are the right fit for header pins.
I also use leftover component leads (typically cut leads from new capacitors that I've installed) quite often. These are usually a little smaller in diameter than proper header pins, but they can still be soldered onto wire ends and used as such. They just don't make as tight of a connection.
And if those are not options, perhaps just buy a random header from a parts distributor (online or local).
Last but not least... if the wires that go to the old sensor are thin enough (but not too thin), then you can simply strip them a bit and twist them, then coat evenly with solder. Then if needed, give them a bit of sanding and straightening to make them as close as possible to header pins. After that, you can just shove them into the connector of the new thermistor.

Thank you for the complete answer, yes I have some non working motherboards and video card, uncluky I always throw away cd rom or hard disk when they don't work, today the seller shipped the sensors I should get in a week, Ill update once I get them so I can check what to use more properly. I need the male side to solder. I tried to check any mark or something else to identify the case but nope, there is no brand at all unlucky.

So I received the sensors today, I think the pin idea it's very wise, I'm just struggling to find them on my broken stash stuff, I was thinking to buy them from aliexpress, would those works fine?
https://www.aliexpress.com/item/1005007078061569.html

Just about any motherboard should have similar header pins like that (even a fan header should work.) Otherwise, the product from the AliExpress link above should work too... I think? (Don't remember if motherboard headers used 2.0 mm or 2.54 mm spacing.)

That's my main concern, the spacing.

Well, if the spacing is too small, just cut the plastic separating the pins and solder each to the wire.
And if the spacing is bigger, you can either bend the pins inwards or you can cut the plastic to separate them and then grind it down between the two points where it was cut so that they would be closer together once put back together.
Or just remove the plastic entirely and solder the headers directly to the wires.
None of these are exactly "neat" solutions compared to a header with the proper spacing... but as long as your inner OCD won't get triggered over little stuff like that (I know mine can sometimes), all of the above should work.

I've received the pins, they fit but they are very thin I'm not able to solder them properly so I did this: I put the wires in the connector and tried to turn on the pc, the temperature are detected correctly, now I just need to find a way to do a better job since push the tiny wires in the connector doesn't seem a definitive solution.

Edit: so it ended up in a disaster. I wasn't able to properly tin the wires (they are very small alluminium or tin wires) and the conseguence it was that I was unable to tin them to the jumper, I ended up with a jumper tinned and the other destroyed. I hate those soldering jobs I don't know if I'm just incapable of doing them or I don't have the proper equipment.