L3 cache read test very inconsistent (Threadripper 3960X + Gigabyte TRX40 Aorus Xtreme)

[Czolgista778]

I've noticed that my Threadripper 3960X is producing very incosistent L3 Cache read benchmark results, one time it's 2000GB/s+, the other time it's below 400, then again 2000, 380, 1500 and so on. 

The configuration is a 3960X, TRX40 Aorus Xtreme, 4x8GB 3200 CL14 RAM, 4x1TB NVMe raid0 array. This happens on both W10 build 1909 as well as on build 2004.

I have already tried updating the drivers, changing the power plans and memory settings. The setting below includes memory OC (albeit 2000% HCI memtest stable) but the stock 3200CL14 results show an identical pattern.

[Fiery]

16 hours ago, Czolgista778 said:

I've noticed that my Threadripper 3960X is producing very incosistent L3 Cache read benchmark results, one time it's 2000GB/s+, the other time it's below 400, then again 2000, 380, 1500 and so on. 

The configuration is a 3960X, TRX40 Aorus Xtreme, 4x8GB 3200 CL14 RAM, 4x1TB NVMe raid0 array. This happens on both W10 build 1909 as well as on build 2004.

I have already tried updating the drivers, changing the power plans and memory settings. The setting below includes memory OC (albeit 2000% HCI memtest stable) but the stock 3200CL14 results show an identical pattern.

On processors that have a large L3 cache that serves a lot of CPU cores, it's very tough to avoid some background process or service to write something into the L3 cache.  There's no real solution to this issue other than re-running the L3 read bandwidth benchmark 10 times or until you get the highest score possible.  Just double-click on the box that is in the row of "L3 Cache" and in the column of "Read" to re-run just the L3 cache read benchmark.