Why do people use the xxxxK Intel Processors if they aren't supported

[cencal2235]

I am just curious as to why people would use the K versions if UnRAID doesn't support the features in them. 

 

I understand if people are just repurposing old parts and PC's laying around but it seems that I have seen many new builds explicitly for UnRAID and they have them. 

I am planning a new system and wondering if I am making a mistake in not getting the K version. 

 

I would assume it is for other tasks that their servers run but just wondering.

[JonathanM]

19 minutes ago, cencal2235 said:

why people would use the K versions if UnRAID doesn't support the features in them. 

Which features are you referring to?

[Hoopster]

1 hour ago, cencal2235 said:

I am just curious as to why people would use the K versions if UnRAID doesn't support the features in them. 

The K just means the processor is unlocked for overclocking.  It's not that unRAID does not support overclocking but it certainly is not recommended for a server as overclocked CPUs can cause server stability issues.

 

The K processors seem to be in greater supply and work fine for unRAID servers without the overclocking.

 

Are you referring to some other K processor feature?

[cencal2235]

Yes, the overclocking is what I was talking about. 

 

Like I said, I am new to this. I know what overclocking is and I was just wondering why some spend the money to get the K version if Unraid doesn't support it. 

 

I am looking to build a new machine and I had completely ignored the K skus because I thought the premium cost for a K was wasted money. I am trying to figure out if I should get the K after reading through some people's builds. 

[ChatNoir]

2 hours ago, cencal2235 said:

Like I said, I am new to this. I know what overclocking is and I was just wondering why some spend the money to get the K version if Unraid doesn't support it. 

It's not that overclocking is not supported. There is as much support than in every other OS. I am pretty sure that if you ask a Windows engineer, he would prefer you don't use an unstable overclock on his OS.

 

The thing is that servers are built to run 24/7 and are supposed to be as stable and reliable as possible. Overclocking is the opposite of that.

 

Now, as why people are still buying K models I see several reasons :

• they are used to when building a gaming rig
• they use their old gaming rig as a server
• K variants often offer higher stock clocks and are generally faster than the non-K model

 

But its fine to use them if you keep the stock clocks and power settings.

[Vr2Io]

The Governor ( dynamic clock multiplier ratio is different for "non-K" & "K" )

 

https://www.intel.com/content/www/us/en/products/compare.html?productIds=191792,186604

 

For example 9700 vs 9700K, clock range are 30-47 vs 36-49, so it's scale is different. In overall, 9700 will consume less power but also a bit slow.

But you can config 9700K ( some BIOS ) in same scale too, so theoretical it can consume same power as 9700. That's flexibility.

 

As different CPU almost use same amount power when idle, so "K" type CPU in normal build also acceptable.

 

[Kilrah]

K models usually have higher base clocks than the non-Ks, so even without manually overclocking you get a bit more performance. 

 

But the reason is probably mostly that there are more Ks around, in my case my server has a 7700K because that's a PC I had previously (that was overclocked an all) that has now been repurposed as server. If people buy used parts they're also more likely to come across Ks.

[ConnerVT]

I'll give a little insight in how the sausage is made.  I've worked in semiconductor manufacturing for the past 20+ years.

 

You do not start out manufacturing 9700 and 9700K processors.  All are built as 9xxx chips, with the goal that all of them run as fast as possible.  At a point near the end of manufacturing (after the individual die have been packaged) they go through a binning process.  This is where they are tested for functionality at speed.

 

In simple terms, the test determines the fasted clock speed the chip will run reliably.  Processors that run at the fastest speed reliably at the "K" specification targets are binned as 9700K.  Those that don't meet those targets, but function at the lower 9700 parameters go in the 9700 bin.  Usually at this time they program the chip internally with the chip its designation (effectively "locking" the clock speed).  There is usually still a bit of headroom given, such that a 3.5 GHz chip isn't going to fail at 3.51 GHz.  Generally, even locked processors have a few 100 MHz extra, allowing the company to be confident that the chip operates at its advertised speed.

 

As @ChatNoir wrote, a server runs 24/7/365.  A binning test runs maybe an few hours.  Running at the edge of a processor's speed for a prolonged time is asking for a failure to occur.  With the 9700K proven to have been manufactured better and having a higher base clock, if it fits your budget the K chips (running at base clock) are probably the more reliable choice.

Edited September 12, 2022 by ConnerVT
Fat Fingers

[cencal2235]

Thank you guys for the info. 

 

I will be getting a K processor after reading all of this.