Strange memtest MB/s X4-945 on GA-MA785GT?

[Pete S]

Hi guys!

I though I'd ask the expert here since I have never really gotten my hands dirty trying to optimize much even though I build my first PC back in 88

Anyways, I have an X4 945 running at stock defaults with two Kingston 4GB DDR3-1333. BIOS says they are in unganged mode which I guess is interleaved dual channel?

Is it normal to get only 3981 MB/s in memtest with an X4-945? I get 8948 MB/s with a i3-530 also running stock settings with the same speed memory (2x2GB Kingston).

Any input would be much appreciated!

Thanks,
Pete

 

[xoke]

WARNING: Theory, only theory...

The AMD has two memory controllers. You are running them in unganged (this is normal and in most scenarios better). In unganged mode they run two 64bit independent data paths, as opposed to a single 128bit data path. For most applications, two 64bit data paths proves better, but perhaps, just perhaps the way memtest "tests" a larger 128bit data path (better for a hige single chunk of data) is better, thus giving your Intel system a better looking "score".

Memtest is a tool, a good tool, but I dunno if I'd rely on it as a benchmark.

EDIT: Ok, my theory is gone, just ran a quick test...memtest gives better numbers when unganged. I have no clue now.

 

[QuietIce]

Just to check can we get a screen shot of the CPU-Z CPU, Memory, and SPD tabs?

Memtest is a tool, a good tool, but I dunno if I'd rely on it as a benchmark.

I agree.

What kind of "score" did you have with your system ...?

 

[Pete S]

Thanks guys.

Unfortunately I have installed linux on the computer so I can't check with cpu-z.

Maybe Phenom II CPUs are just much slower than Intel when it comes to memory transfer speed or memtest can't properly report the true transfer speed. Everything seems to work OK though even if I possibly are running some kind of single channel mode.

It would be interesting to know what you guys are getting in memtest transfer speed? Maybe the numbers are perfectly normal?

 

[QuietIce]

I started to run a MemTest on my 940BE last night then realized I don't have an optical drive hooked up to it right now. I run a lot of caseless SETI crunchers so a DVD is strictly optional. I can access DVDs over the LAN but I doubt I can boot from one like that.

Maybe someone else will post their results. I've got plenty of memory bench results for all my systems but, as xokeman said, MemTest isn't exactly a benching program. Maybe sometime over the weekend I can hunt down my spare DVD and hook it up ...

 

[Pete S]

Thanks QuietIce.

I know what you mean about optical drives since they are seldom used. I got myself one of those slim Samsung DVD burners that run on USB power. They're actually pretty good and perfect for booting.

I also have one of those USB driven Sony 3.5" floppy drives for the extremely odd occasion

 

[QuietIce]

That's not a bad idea! Next time I get a DVD I'll try one of those USB units. I can use my spare in the new rig and keep the USB as the spare ...

 

[Neuromancer]

I hae never seen accurate numbers from etest on AMD... compare it to sissoft memtest of everest or something and see for yourself.