New 9900k build system interrupts

tintin82 · 27 May 2020 at 15:32

Hi folks,

I could really use your help with a very frustrating problem with my new build.

I just purchased a 9900k and Z390 Aorus Pro second hand (I have no reason to believe there is any problem with them as I met the previous owners and was given the receipt for the CPU.)

I built the new system and was very impressed when I overclocked it easily to 5GZ with simply entering a 50 multiplier and 1.32v, LLC turbo. All worked great, stress tested with IBT and Prim95, not problems, temps mid 80's. Played a few rounds of BF5, no problem.

Then I noticed that randomly the CPU load would spike to near 100% and the system become extremely sluggish. Using Process Explorer I found that System Interrupts was the culprit. The high CPU usage lasts for about 2 mins and then subsides. This has happened about four times in the past two days, with no common denominator, but I think its mostly when on the desktop.

I have installed all the chipset drivers from the Gigabyte website, but not change. I now plan to disassemble and rebuilt the system in case I have a loose connection.

Is there any advice anyone can offer? The internet has plenty of details about this problem, but no real solution.

Anyone know what the cause might be? Most likely driver, unstable overclock, or faulty motherboard / CPU?

Thanks for your help

timmy222 · 28 May 2020 at 09:34

The System Interrupts process should not use too much CPU power (normally, up to five percent), however, some users have reported excessive CPU usage by this process. High CPU usage caused by System Interrupts usually means that a hardware driver is not working properly or there is an issue with the hardware itself.

Puppetmaster · 28 May 2020 at 11:18

Did you reinstall Windows with the new parts or just use your existing install?

tintin82 · 28 May 2020 at 13:39

Puppetmaster said:
Did you reinstall Windows with the new parts or just use your existing install?

Fresh install. I have refitted the gpu and reinstalled the drivers. The GPU was very slightly misaligned as I found the PCIEX clip was missing. There has been no repeat occurrence for the last 18 hrs, but early days. Worried I might have bought a duff board, but I can play BF5 for a few hrs and all it good.

tintin82 · 31 May 2020 at 07:16

In case anyone stumbles over this thread later the issue may have been a gremlin. I refitted the RAM, nvme, and GPU. Issue did not happen again.

BUDFORCE · 31 May 2020 at 13:40

It's amazing how this can happen.

You'd think the hardware would either be connected and working, or not connected and not working.

However, a surprising amount of hardware issues are caused by hardware not being properly seated yet still 'sort of' working.

Normally RAM, but graphics card or anything really.

tintin82 · 31 May 2020 at 21:16

BUDFORCE said:
It's amazing how this can happen.

You'd think the hardware would either be connected and working, or not connected and not working.

However, a surprising amount of hardware issues are caused by hardware not being properly seated yet still 'sort of' working.

Normally RAM, but graphics card or anything really.

Tell me about it! Years ago I had a system crashing randomly, BSOD multiple times a day. Took me ages to find the culprit.... a bit of fluff stuck in one of the SATA ports where my OS SSD plugged into.

Another one I had was a network card that kept crashing and dropping out. Again, days of stressing and troubleshooting, fresh install, testing drivers... only to find the reason was a old network cable that must have had damaged internals as once changed it worked 100%.