3.8GHz Prescotts....

[mostlyscsi]

Hello-We are new to the DFI forum!

 

We have an 875P-T motherboard-lots of interesting features.

we have some problems which may be a result of the CPUs.

First off, we started witha 3.6GHz CPU, and hit 237FSB(HyperX 4000), and as soon as you go to 238, the "ODA" speedometer reads 17MHz!

This happened regardless of this cpu, or another(a 3.4"EE"LGA-775) .

Voltage changes made no difference(we also use a micro frezer for coolimg, my son says its called a "Mach-1?")

Changes to differnet brands of RAM, and going to 4400 made no difference.

Any ideas?

 

Secondly, we put in a 3.8GHz CPU, and it will not work at all over 200 FSB. NO voltage increses of any sort, in any amount will allow a "boot". This cpu seems not to be able to "overclock", is there something different about the 3.8GHz CPUs?

We upgraded the BIOS courtesy of DFI helpline to a March 25th date(?) at least the machine now starts(precious to this, it would not even boot with the 3.8!)

 

We use x850xt Paltinum for video.

My son said to mention that his chips are "confidentials" Is this significant? He says that they are called: "engineering samples." The yare supposed to be : better?

 

If so, I can't see anything other than trouble! The fact that the 3.6 did 237(but ONLY up to 237, and the 3.8 can't ghet over 20, says something is very wrong.

He has a 3.4 EE that goes to 250FSB(al beit in an ASUS motherboard), so something seeems very wrong with these CPUs.

Is there something that he does not know about in the DFI BIOS which is preventing him from being able to go "drag racing" with his buddies?

Any and all help would be hugely appreciated!

Does he need to download additionale "stuff" to get his FSB to get past 237 on the 3.6, and to get out of 200 on the 3.8?

 

Again, any and ALL help will be hugely appreciated!

Tyhank you, Craig

[MikeyLikesItSI]

I've never been able to go higher then 240 with CPC addr control enabled. Under the advanced menu with the memory timing options, towards the bottom of the list is the option. Try disabling it and see what happens.

[red930]

Engineering Sample (ES for short) CPUs claim to fame is they have adjustable multipliers (i.e. 3.6Ghz ES - 14x through 18x; 3.8Ghz - 14x through 19x). What most people who overclock these CPUs will do is drop the multiplier down to 14 or 15 and raise the bus speed. As you can see from my sig, I am running the CPU at a 15x multiplier with a bus speed of 284Mhz. I am having to run the RAM at 5:4 divider to get to that speed as my Mushkin PC4400 is not quite up to the task of handling that great of a load.

 

Try MikeyLikesIT's suggestion for disabling the CPC Address Control. Turning that off has a great affect at increasing your overclocking success.

[fordf250]

And put the Vagp up also.

[MikeyLikesItSI]

I'm starting to think the VAGP isn't a necessity. I'm hanging out with the current voltages at 270FSB

 

vmem 2.7,

vagp 1.6,

vcore 1.450

 

I think the N/B cooling is more important then VAGP. I'm leaning away from doing that VAGP mod, and i'm going to find a better method of supporting this water block on the northbridge. I can control the error count/speed in memtest by holding the block in different positions.

[fordf250]

Mike I saw your post on holding the NB cooler down better.Good Idea.When I was doing the 5/4 divider stuff all I needed was 1.6Vagp for 290fsb but I remember when I got this board I needed more Vagp to get over 266 1/1 so I always put it up. Mabye something has changed with the new bios.