PC Doesn't boot with new CPU | Please help

[AspireOne]

So I switched from i3-7100 to i5-9600KF and the computer doesn't boot up with it. The PC stops booting so fast that the fans don't even start spinning.

I'm 100% sure it's caused by the CPU - I switched the old and new cpu several times without changing any other component -> the old works and the the new doesn't.

 

I updated my bios and resetted CMOS, but still no luck. I'm honestly pretty scared that it won't work and I don't know what to do.

 

Edit: My motherboard is Acer GX-781 (KBL)

[SupaKomputa]

Just now, AspireOne said:

i3-7100 to i5-9600KF

that's not compatible with the motherboard im afraid.

[AspireOne]

1 minute ago, SupaKomputa said:

that's not compatible with the motherboard im afraid.

Why? How do you know? The socket is the same, is there anything else that I had to make sure is compatible?

[Skiiwee29]

Check your Motherboards supported CPU list, it will only be the 6XXX and 7XXX series only. Intel really messed up a lot of consumers by using the same socket for multiple generations. 

[AspireOne]

1 minute ago, Skiiwee29 said:

Check your Motherboards supported CPU list, it will only be the 6XXX and 7XXX series only. Intel really messed up a lot of consumers by using the same socket for multiple generations. 

I thought that the "supported components" list is always incomplete and not up-to-date and that it's just some recommendations. Jeez I can't believe it... This is terrible. I hope they'll let me return it...

[Skiiwee29]

1 minute ago, AspireOne said:

I thought that the "supported components" list is always incomplete and not up-to-date and that it's just some recommendations. Jeez I can't believe it... This is terrible. I hope they'll let me return it...

not when it comes to CPUs its not. Other stuff will be, but CPUs wont ever not be accurate. 

[SupaKomputa]

56 minutes ago, AspireOne said:

I thought that the "supported components" list is always incomplete and not up-to-date and that it's just some recommendations. Jeez I can't believe it... This is terrible. I hope they'll let me return it...

No don't return it, i suggest you get a cheap motherboard instead, sell your old board.

With that motherboard you simply have limited choice to upgrade.

Check the compatibility here:

https://pangoly.com/en/review/intel-core-i9-9900k/compatibility/motherboard

[Beerzerker]

1 hour ago, AspireOne said:

Why? How do you know? The socket is the same, is there anything else that I had to make sure is compatible?

The actual pinout of the pins in the socket are different related to what each pin is for;  Voltage, ground and so on.
Socket 1151 simply means it has 1151 pins in it and that's used as a basis for the chip design but doesn't mean all are alike.

For best results I too suggest a different, compatable board if you can.


 

[AspireOne]

1 hour ago, Benji said:

Because Intel said so, and the socket 1151 actually has two versions of it that are, according to Intel officially at least, not compatible with each other. There's socket 1151 and 1151v2. The Intel 9*** series desktop processors are Coffee Lake Refresh processors that only work in the 1151v2 with 300 series chipsets. The KBL in the Acer prebuilt's product name denotes the 100 Series chipset (Skylake (6*** series processors) and Kaby Lake (7*** series processors), 1151"v1") and thus supports Skylake Kaby Lake only (7*** series processors). If you want Coffee Lake you'll need a 300 series chipset and if you want Coffee Lake Refresh (which is what your CPU is), older 300 series motherboards will need a BIOS update to support them (unless it's a B365 or Z390 chipset).

So your board won't support them. The highest you can put in your Kaby Lake build will be the 7700K.

It's just stupid how cryptic this is. Even now when I'm trying to find info about it on purpose, I can't find any.
Thank you

[Beerzerker]

31 minutes ago, AspireOne said:

It's just stupid how cryptic this is. Even now when I'm trying to find info about it on purpose, I can't find any.
Thank you

It's not that cryptic.
I explained the basics of it in my post above, the functions of the pins in the socket were changed with the revision of these chips. That means for example, a particular pin that was intended to be a ground with V1 is a pin for power with V2.
Although the pin number count (1151) itself didn't change and the physical size / shape of the chips didn't change, the functions of some individual pins did.

That's why your system is cutting off instantly when you press the power button, the system is detecting a short and doing a hard shutdown to protect itself.
It was simply Intel pushing these changes to drive sales of their chips and so board vendors could do the same at the time they were being made.