Core i5-7500T: too hot??

[highpost]

I have embarked on my first build: a fanless Mini-ITX system for browsing, writing and developing.

• 
  ■ CPU: Core i5-7500T
  ■ motherboard: ASRock H270M-ITX/ac
  ■ memory: 2 DDR4 PC4-17000 UDIMMs
  ■ storage: 512GB M.2 NVMe SSD (Samsung)
  ■ case: Antec ISK110-VESA

With its 35W TDP, the Core i5-7500T is the centerpiece of this build. According to fanlesstech.com, the T series are "basically the ideal processors for passive cooling.”

Today I built up the system, booted it and switched into the BIOS. And then I watched the CPU temperature, hoping to feel good. I did not feel good. I watched the 7500T immediately jump to 67 C and then steadily rise to 75 C until I called it a day. The junction temperature for this CPU is 80 C.

Note that I did not attach any cooling system, active or passive, to this CPU. So my first question is whether that is necessary for this kind of a system? I can see three scenaries here:

• 
  ■ active cooling: of course this would work, but there go my plans for a fanless system
  ■ passive cooling: these devices seem to be very large and/or expensive
  ■ bad CPU: is this kind of temperature buildup excessive or is this pilot error?

Finally, if I do need a compact passive cooler, can you recommend a device?

Thanks for your help.

 

[MrN1ce9uy]

You mean you don't even have a passive heatsink block attached to the CPU? THat's your problem right there. Of course you need at least some sort of cooling solution.

 

[lumineZ]

What in the world?
Are you really running the CPU without any heatsink at all?????

NO cpu out there can be used without some kind of a heatsink, passive or active.
If you dont have a heatsink how would you expect the CPU to get rid of its heat in the first place??

 

[dudeman509]

Wat.

Even Raspberry Pis and smartphones have passive cooling in the form of a heat spreader or cooling fins.

 

[highpost]

Okay, now I'm trying to assess my options. When choosing power supply you count up the power requirements for your components, perhaps add some headroom for future expansion and you have an idea of how big your PSU needs to be.

Cooling is different. Now I (clearly) don't understand how to characterize the heat dissipation requirements for this system. I can look on pcpartpicker and see pages of active cooling systems (fans), but I don't have a heat *number* that tells me how much cooling I need. And can I do this with a smallish heatsink?

Thanks again.

 

[dudeman509]

You need to dissipate ~35W of heat from the CPU. Plenty of passive coolers can handle that. The H270 motherboard TDP is ~6W.

You'll also need to move air/heat out of the case itself. Very quiet fans or a very open case would help do so, but really, that entire build without a GPU will generate very little heat - on the level of an older Ivy/Sandy Bridge laptop.

PSU requirements are quite minimal as well. A 200-300W unit would be more than enough (honestly a laptop charger would cut it)

 

[highpost]

The Antec ISK110-VESA has a built-in 90 watt PSU, which is more than enough for my CPU, motherboard, RAM and SSD. It also has a perforated mesh cover to help with the heat dissipation, but it's very small. So I think I have about 2 in of clearance to work with. So for example, the ARCTIC 11 won't fit.

The good news is that the CPU came with a fan, so I can use that while I figure this out.

Again, any specific suggestions of a heatsink would be much appreciated.

Thanks for your help.

--Dan

 

[mdd1963]

It may be fanless, but, *of course* it needs a heatsink, with a fan somewhere blowing across it or pulling air thru it..., or both...