4x512MB on P4C800 Dlx and more things on ASUS BIOS... :(

[bcn]

So I had the opportunity to run 4 sticks of 512mb each (all OCZ PC-3500 Dual channel) on my P4C800 Deluxe.
as someone here in the forums told that Canterwods are optimised for 4 mem sticks...

Well, I wanted to see the difference in memory bandwidth... AND I discovered one more thing on ASUS... :(

It seems that BIOS automatically disables PAT if all the memslots are populated and it enables if there are two dimms... though in BIOS you select it as enabled...

So now we know:
1. that PCI/AGP frequency is bluff in this board BIOS, as it always sets for 66/33.
2. PAT selection is also for your eyes only here.
3. 2.55V and auto for memory voltage do not work and it sets to 2.68V

some have reported that the voltage for CPU did not work for them at above 1.6V

Maybe there are people who know some more "bugs" like that...

ANYWAY, here are the pics:

[bcn]

and the picture with for sticks installed.

By the way, the difference in the scores is due to PAT enabled/disabled.

hey, maybe someone has the board there that can test is there really any difference in mem bandwidth with 4 sticks vs. 2

[Major]

Thanks for the info !

How do you know that PAT is disabled ?? does it show in bios as disabled ??

I was able to use up to 1.725v on my P4C800, but I have heard that several people had problems with higher vcore settings.

[bcn]

that is the point, that in bios we even do not have this option, we have enabled and auto, but no disabled. though setting "Performance acceleration mode" in BIOS to any of these settings gives you the same results:

2 sticks - enabled
4 sticks - disabled

and it does not matter what you put there in bios... :(

I really start to dislike asus for these things they do... :(

[Zroc]

PAT is not disabled...Sandra is just incorrect.

There is no possible way to disable PAT on an 875P chipset...it is always on the PAT path, period.

The only thing installing four sticks will do is disable dynamic mode, which is not the PAT path.

[TechTones]

Well

I have 4 x 256mb sticks of HyperX 3500 in a P4P800.

With 2 sticks I can do 233 cas2

With 4 sticks it doesn't seem as stable at all. I can't even get it to 226 cas2 stable. In fact, even at cas 2.5 it won't boot at 233.

I don't know if it's the 4 dimm's being populated, or the board can't handle it, or it's not enough Vdimm at 2.85v

If I stress the system and the ram is at 226, the system just shuts down. 2 sticks do 233, 4 sticks suck....

[daddy_fizz]

it might be one of your sticks isn't on par with the other 3 and is holding them all back...

just my idea, i've had some similar problems before...

~Fizz

[TechTones]

I was thinking that also.

I can tell you one thing that mobo makers need to take heed to, is that when all slots are used you need more Vdimm to get to perform stable or as well as only 2 x 256