NextGen VS. CurrentGen CPU: 3DMark06

[Kasparz]

Why you can't run Phenom with normal ram speeds and timings?

[metro.cl]

Why you can't run Phenom with normal ram speeds and timings?

Maybe divider issues since they run Phenom at 3.0GHz and that is definetly overclocking it (like 20%+)

[expreview]

Maybe divider issues since they run Phenom at 3.0GHz and that is definetly overclocking it (like 20%+)

yes. the Phenom was oc on 200MHzX15,and the RAM frequency would be:

3000/7=428.57MHz or 3000/8=375MHz.

[justapost]

yes. the Phenom was oc on 200MHzX15,and the RAM frequency would be:

3000/7=428.57MHz or 3000/8=375MHz.

Is 3000/6=500MHz with 1066 DDR2 not possible?
Why is the northbridge running at 16000MHz, like on a non split power board?
ES issue?

[GoThr3k]

Why is the northbridge running at 16000MHz, like on a non split power board?
ES issue?

i was thinking same thing

[generics_user]

i don't believe that this runs on a RD790 board

just look at the NB frequency, do they use ganged or unganged IMC mode? (che k kyosens thread for more info on this) , their ram freq is weird (K10 doesn't derive mem clock from core speed like itt used to be on K8), the timings are not OK.

[JumpingJack]

Maybe divider issues since they run Phenom at 3.0GHz and that is definetly overclocking it (like 20%+)

It is precisely the memory divider issues, any non-even CPU multiplier will down clock the memory at stock system clock speeds (200 MHz). Don't you feel cheated

This is a well known phenomena (pardon the pun) of AMD's memory controller, most AM2 reviews made note of this:

Example: http://www.anandtech.com/cpuchipsets...px?i=2762&p=10

For a multiplier of 15, the fastest a Phenom will clock DDR2-800 will be 375 Mhz not 400 Mhz.... so what you see is what you are gonna get. To get 400 Mhz on the ram, you will need to force the DDR2-800 ram to 428 (i.e. 3000/7 = 428 and thus risk stability) or buy DDR2-1067 and force it do DDR2-800 (i.e. 3000/7 = 428 running psuedo DDR2-856), but then you would probably want to multiply that memory up to to closest to 1067 as you can get, but it too will underclock it's full rating.

Everyone should note -- if you purchase an AMD CPU with a non-even CPU multiplier, the memory will be down clocked from it's best possible... this is just the way the AMD memory controller works.

The short answer -- the memory speed reported above is exactly where you would expect an AMD CPU to run DDR2-800 memory with a CPU multiplier of 15...

Jack