Core Duo 2 (Conroe) and Chipset 955X Why NOT?

iampowerslave

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Dec 23, 2004
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Hi,

I've searched for this on the forum, but have not found a thread/post about it.

Does anybody knows why Core Duo 2 are not (will not?) run on 955X chipset?

What's the damned difference between 975X and 955X excluding the 2*16x PCI-Express?

Thanks for your answers.
 
I remember reading somewhere that this was something to do with it missing something really small, like a plug for something to do with a power saving mode of some sort. It sounded really pathetic, sorry that I cant bring up the article off hand, someone will though.
 
i don't see why it isn't possible for i955 to work w/ conroe except for the voltage issue someone mentioned. but one would think a simply bios update would fix that.

i think the reason is more economical. currently intel has two chipsets planned for conroe, i965 and i975. historically, intel hasn't really supported more than 2 chipsets for any generation of CPU. the exception would probably be northwood where the i850, i865 and i875 were all compatible. but the reasoning for that was more of a memory issue (we had rambus and DDR competing back then). let us not forget that nVidia and ATI have their own chipsets planned. so eventually the motherboard market is going to be flooded with competing chipsets for Conroe. Adding yet another chipset (i955) would be too much I think.

anyways, point is, intel doesn't want to support any additional chipsets if they don't have to. and they don't really have it.
 
I believe it is because the 955x does not support a voltage LOW enough to support Conroe, i'll dig out some information on it for you later.

That would make sense since it is the issue with the current (not new) 975 motherboards. Pretty much it looks like you ahve to buy a new motherboard for Conroe, even if you ahve a "supported" chipset (unless I am wrong, I think the only work around is to do a little soldering on the MB yourself).
 
It has to do with the sensors used with Conroe called PECI (Platform Environment Control Interface). Here is the link. If Conroe can't sense this on the mobo, then the system won't boot. This is the modification that has to be made to 975 chipset mobos in order to work with Conroe. I suppose if the power requirements were not an issue, then a 955 chipset board could be modified too.
 
Just need to do your homework when you find 975 board it seems.

I suppose this is actually one reason why some 975X chipsets will not work, like for the Abit AW8D:
a new motherboard with a PWM refresh is required for these new Conroe pocessors
I suppose the PWN refers to, the power management. or perhaps it is actually pulse width modulation. Not exactly sure.

I was a lil dissappointed that abit MB wouldn't run conroe because of that. Its fairly a new MB.
 
Hi,

I've searched for this on the forum, but have not found a thread/post about it.

Does anybody knows why Core Duo 2 are not (will not?) run on 955X chipset?

What's the damned difference between 975X and 955X excluding the 2*16x PCI-Express?

Thanks for your answers.

It all comes down to the Voltage Regulator on the motherboard. These have been progressing as time goes on. The latest is labeled VRM 11. To run a Conroe on any motherboard it will need to have VRM 11 Vreg. The difference between the Bad Axe and Black Creek motherboard is the Bad Axe -304 rev boards have VRM 11 Vreg implimented while the Black Creek motherboard has the older VRM 10.

The big difference between the VRM 10 and VRM 11 Vreg is final Voltage control. This is to match the input voltage that the processor ie(Conroe) is expecting. If you did put a Conroe into a Black Creek board I'm betting it would not even turn on.

When you turn on the power to the board it checks to see if the right voltage is supplied and determines if the board can support it. If it does not it just sends a signal to the Power Supply to shut down.
 
let us not forget that nVidia and ATI have their own chipsets planned. so eventually the motherboard market is going to be flooded with competing chipsets for Conroe. Adding yet another chipset (i955) would be too much I think.
That's the best possible explanation. But If a manufacturer wanted to add Conroe support to the 955 chipset, they would. They've already done it with the 945 and 865 chipsets. There just doesn't seem to be the demand.