When I start my pc the cpu is at max heat

[Jopium7711]

I recently upgraded my i5-9400f into a i7-9700k 

but when I started my pc my fans suddenly started going crazy and I checked my cpu and apparently it’s using 100% of it.

is there any fix to that issue or did I get a cpu that’s not supported by my motherboard?

[resistencia]

Hi @Jopium7711 

It is a processor with a TDP of 95 watts, I do not think it is compatible with your models, the HP certified processors are the following.

• TDP: up to 65 W
• Socket type: LGA1151
• Motherboard supports the following processor upgrades:

  Processor	TDP
  Intel Core i9 9900 3.1 GHz base frequency, up to 5.0 GHz with Intel Turbo Boost Technology, 16 MB cache, Octa core (Coffee Lake-R)	65 W
  Intel Core i7 9700 3.0 GHz base frequency, up to 4.7 GHz with Intel Turbo Boost Technology, 12 MB cache, Octa core (Coffee Lake-R)	65 W
  Intel Core i7 9700F 3.0 GHz base frequency, up to 4.7 GHz with Intel Turbo Boost Technology, 12 MB cache, Octa core (Coffee Lake-R)	65 W
  Intel Core i5 9400 2.9 GHz base frequency, up to 4.1 GHz with Intel Turbo Boost Technology, 9 MB cache, Hexa core (Coffee Lake-R)	65 W
  Intel Core i5 9400F 2.9 GHz base frequency, up to 4.1 GHz with Intel Turbo Boost Technology, 9 MB cache, Hexa core (Coffee Lake-R)	65 W
  Intel Core i7 8700 (Core i7 and 16 GB Intel Optane memory) 3.2 GHz base frequency, up to 4.6 GHz with Intel Turbo Boost Technology, 12 MB cache, Hexa core (Coffee Lake-S)	65 W
  Intel Core i7 8700 3.2 GHz base frequency, up to 4.6 GHz with Intel Turbo Boost Technology, 12 MB cache, Hexa core (Coffee Lake-S)	65 W
  Intel Core i5 8400 (Core i5 and 16 GB Intel Optane memory) 2.8 GHz frequency, up to 4.0 GHz with Intel Turbo Boost Technology, 9 MB cache, Hexa core (Coffee Lake-S)	65 W
  Intel Core i5 8400 2.8 GHz frequency, up to 4.0 GHz with Intel Turbo Boost Technology, 9 MB cache, Hexa core (Coffee Lake-S)	65 W
  Intel Core i3 8100 3.6 GHz Base frequency, 6 MB cache, Quad core (Coffee Lake-S)	65 W

[NonSequitur777]

@Jopium7711,

What you need to do is to replace the 65-watt TDP CPU heatsink with a better heatsink, such as this purchase example via Amazon-Germany: be quiet! Pure Rock 2 Black, CPU Cooler, 150 W TDP, Pure Wings 2 120 mm PWM, 4 x 6 mm Heat Pipes, As....

And yes, all 9th-gen Intel processors with 95-watt TDPs, such as your i7-9700K and an i9-9900K are fully compatible with your OMEN by HP 875-1000 Obelisk Desktop PC (3VH40AV) as fitted with the Shire motherboard (SSID: 8509), as you can see here amongst HP System OMEN by HP Obelisk Desktop 875-1xxx Users: UserBenchmark: HP OMEN by HP Obelisk Desktop 875-1xxx Compatible Components.

Only hassle is that you'll have to take out your motherboard in order to remove the backside CPU bracket as outlined, because these replacement heatsinks use their own proprietary socket bracket:

Kind Regards,

NonSequitur777

[NonSequitur777]

@Jopium7711,

As for your cooling fans going crazy, I would temporarily reinstall your previous processor, and making sure you got the latest BIOS version F.35 Rev.A (Dec 29, 2023) :

Link: OMEN by HP Obelisk Desktop PC 875-1000i Software and Driver Downloads | HP® Support.

[EDIT:] I would also carefully inspect your i7-9700K, making sure it is clean (preferably clean it gently with a Q-tip dipped in 99% isopropyl alcohol) and does not appear to be damaged:

In addition, I would also inspect the CPU socket on your motherboard, making sure that there are no bend pins and/or debris.  Use compressed ("canned") air to blow out the socket.

Once you got that, install the i7-9700K (using a quality thermal paste such as Arctic MX-4), remove all peripherals except your monitor and mouse/keyboard, plug in power, and push your power button for several seconds until your PC powers on and off again, and repeat this once more.

If the same run-away fan issue happens, reset CMOS: power off, remove power, push your power button for 4 seconds in order to release any residual power, and remove your CMOS battery for 10 minutes.  Reseat CMOS battery and start up again.

Report back.

Kind Regards,

NonSequitur777

[jorell1]

the omen seems to have an issue ..retrace your steps before installing the card and make sure no power is on the board

unplug computer and hold power button in for 20 sec make shuere al power is drained  check to see if graphics card needs power cable if power supply doesen't have one you may need to convert a sata rail to support the card  not same one already attached

[jorell1]

disreguard  previous post thought you said graphics car ....K series processor is not supported in the computer

[resistencia]

Hi @Jopium7711 

My recommendation before making any changes is to go into Power Options and see if you can configure the TDP, if possible lower the TDP and see if the temperature goes down,

[NonSequitur777]

@jorell1,

Not so: "K" processors are not only compatible on this system, but they are also the top number #1 and #2 installed CPUs:

There is a difference between HP omitting certain processors as being compatible, and which ones are compatible.  Even though I couldn't find any OMEN by HP Obelisk Desktop 875-1xxx Users who installed an i9-9900KS (127-watt TDP), I would bet you could -providing of course, that you install a beefy air cooler or AIO to deal with the extra heat this processor generates.

Kind Regards,

NonSequitur777