# Intel Sandy Bridge L3 Cache Disabled

## Evilguru

Hello,

I have recently purchased a Core i7 (Sandy Bridge) based system.  Upon running lshw I was alarmed to discover:

```

     *-cpu

          description: CPU

          product: Intel(R) Core(TM) i7-2600K CPU @ 3.40GHz

          vendor: Intel Corp.

          physical id: 4

          bus info: cpu@0

          version: Intel(R) Core(TM) i7-2600K CPU @ 3.40GHz

          serial: To Be Filled By O.E.M.

          slot: LGA1155

          size: 3431MHz

          capacity: 3800MHz

          width: 64 bits

          clock: 100MHz

          capabilities: x86-64 fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt aes xsave avx lahf_lm ida arat epb xsaveopt pln pts tpr_shadow vnmi flexpriority ept vpid

          configuration: cores=4 enabledcores=1 threads=2

        *-cache:0

             description: L1 cache

             physical id: 5

             slot: L1-Cache

             size: 256KiB

             capacity: 256KiB

             capabilities: internal write-back unified

        *-cache:1

             description: L2 cache

             physical id: 6

             slot: L2-Cache

             size: 1MiB

             capacity: 1MiB

             capabilities: internal varies unified

        *-cache:2 DISABLED

             description: L3 cache

             physical id: 7

             slot: L3-Cache

             size: 8MiB

             capacity: 8MiB

             capabilities: internal unified

```

Is lshw talking nonsense or is the cache really disabled?  (How can I find out?)

Regards, Freddie.

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## mattst88

I see it too on my 2500K with Asrock H67M motherboard:

```
        *-cache:0

             description: L1 cache

             physical id: 5

             slot: L1-Cache

             size: 128KiB

             capacity: 128KiB

             capabilities: internal write-through unified

        *-cache:1

             description: L2 cache

             physical id: 6

             slot: L2-Cache

             size: 1MiB

             capacity: 1MiB

             capabilities: internal write-through unified

        *-cache:2 DISABLED

             description: L3 cache

             physical id: 7

             slot: L3-Cache

             size: 6MiB

             capacity: 6MiB

             capabilities: internal write-back unified
```

I'm going to do some research.

----------

## whig

What does /proc/cpuinfo say about cache?

----------

## mattst88

```
cache size   : 6144 KB
```

----------

## <3

I am getting the same output on my sandy bridge laptop. On my Nehalem (Lynnfield) desktop it doesn't say that the L3 cache is disabled.

----------

## whig

I checked on my i3 2100T, seems fine here. It's running a vanilla kernel. Cache may be disabled in the bios but it would be strange to do so. Often a bios has reset to optimized defaults option.

```
     *-cache:0

          description: L1 cache

          physical id: 4

          size: 128KiB

          capacity: 128KiB

          capabilities: internal varies

     *-cache:1

          description: L2 cache

          physical id: 5

          size: 512KiB

          capacity: 512KiB

          capabilities: internal varies unified

     *-cache:2

          description: L3 cache

          physical id: 6

          size: 3MiB

          capacity: 3MiB

          capabilities: internal varies unified
```

----------

## roarinelk

 *mattst88 wrote:*   

> I see it too on my 2500K with Asrock H67M motherboard:
> 
> ```
>         *-cache:0
> 
> ...

 

This looks like a dump of DMI data, which is IMO a very unreliable source

of system information.  A better source of cache information is the

/sys/devices/system/cpu/*  tree, it has a few cache/ subdirs.

----------

