• Competitor rules

    Please remember that any mention of competitors, hinting at competitors or offering to provide details of competitors will result in an account suspension. The full rules can be found under the 'Terms and Rules' link in the bottom right corner of your screen. Just don't mention competitors in any way, shape or form and you'll be OK.

Phenom II 955 Memory Speed - A Question

Associate
Joined
19 May 2004
Posts
939
Location
Horsham, West Sussex
I've been looking at the Phenom II 955 BE and I notice in the spec it says

Integrated Dual-Channel Memory Controller with up to DDR3-1333 support

Does this mean if I get 1600MHz memory, I will only be able to run it at 1333MHz?

I also notice that a lot of the AM3 MoBos are rated at 1333 but also state 1600(OC) and 1800(OC). What does that mean?

Cheers,

Nigel
 
Caporegime
Joined
26 Dec 2003
Posts
25,666
It depends on how well the memory controller on the CPU overclocks as to whether you can run DDR1600, even if the motherboard and memory support it if the memory controller can't handle it then it'll be unstable.
 
Associate
OP
Joined
19 May 2004
Posts
939
Location
Horsham, West Sussex
So is the memory speed not set by a seperate ratio like on my current intel system?

So how does it work?

I think the 955 runs stock at 16x200 = 3.2G

If you overclock at 16x225 = 3.6G

does the RAM overclock by the same ratio

Cheers,

Nigel
 
Caporegime
Joined
26 Dec 2003
Posts
25,666
Yes it is linked to the base clock and you've got a few ratios, so yes if you increase the base clock to 225Mhz and leave the ratio the same then the memory will overclock.

With a Phenom black edition though the multiplier is unlocked so you can just increase the multiplier and leave the base clock at 200Mhz allowing all the standard memory speeds (1066/1333/1600).
 
Last edited:
Soldato
Joined
19 Dec 2003
Posts
7,211
Location
Grimsby, UK
Just get 1333mhz @ 7-7-7-24
Nelly said:
Graphics Card: GTX 295

CPU: AMD Phenom II X4 955 Black Edition @ 3.6GHz (3.8Ghz = add extra 2 fps)

Ram: OCZ Blade Series 6GB (3x2GB) DDR3 PC3-16000 Triple Channel (Tested at various timings using 2x2GB) / OCZ Platinum 4GB (2x2GB) DDR3 PC3-10666C7 1333MHz Dual Channel (SAME RESULTS)

Crysis 1600mhz 7-7-7-24 = 54.98 fps

Crysis 1333mhz 7-7-7-24 = 54.43 fps

Crysis 1333mhz 6-6-6-24 = 54.87 fps

Crysis 1333mhz 9-9-9-24 = 52.98 fps
 
Associate
OP
Joined
19 May 2004
Posts
939
Location
Horsham, West Sussex
Thanks for the advice.

Just get 1333mhz @ 7-7-7-24

That makes some sense and I've just been reading up on the latency vs bandwidth.

But there doesn't seem to be much about.

I preseume that if you run 1600 at 1333 then you can tighten the timings in line with 1333 RAM.

Cheers,

Nigel
 
Soldato
Joined
19 Dec 2003
Posts
7,211
Location
Grimsby, UK
I preseume that if you run 1600 at 1333 then you can tighten the timings in line with 1333 RAM.

Cheers,

Nigel
The OCZ AMD Edition 1600mhz @ 7-7-7-24 would drop down to 1333mhz @ 6-6-6-24, I know this for a fact as I had some. :)

If you get any decent 1600mhz @ 7-7-7-24 they should do but not much difference in gaming so no point.
 
Back
Top Bottom