Hammer - RAM questions

[Ilmater]

I'm buying an intermediary board - y'know, until Hammer comes out, DUH - and I'm not sure about the RAM. First of all, I can sell the board and proc to a friend, so that's not a concern. However, it's a SiS 735 board (F*** YOU VIA!), so it can support SDRAM and DDR SDRAM.

My question is, what type of memory will the first Hammer chipsets support? If I got a stick of DDR400 CL2 now, will I still be at the top of the class when Hammer boards come out? It's probably also worth mentioning that I won't be buying a Hammer until around January, assuming that they come out in December. I won't buy a brand new proc because:

A) The prices are too high right at first, especially with the low supply the Hammers will come in, and
B) All of the first-round chipsets will be out in December. By mid-to-late January, they should have at least some of the kinks worked out of the chipsets/mobos (PLEASE MAKE A HAMMER BOARD QUICKLY NVIDIA OR SiS!!!). Even if they're pretty much good to go right after they come out, the best boards (read: Chaintech Apogee 7VJL) don't come out right at first. First the you-need-a-mobo-and-are-willing-to-buy-any-piece-of-shit-I-am-willing-to-give-you mobos, and then the everyone-has-a-mobo-with-this-chipset-but-they-don't-have-a-black-PCB-gigabit-ethernet-gold-chipset-heatsink-rounded-IDE-cables-and-built-in-RAID mobos come out. Those are the ones I'm looking for.

Anyway, I don't want to buy a stick of PC3200 CL2 DDR, only to have it be a mediocre stick of RAM by January. I know that back in March that would have been a ridiculous idea, but RAM innovations aren't exactly flying out of the door right now like they were then.

Also, I figured that since the Hammer had an integrated memory controller, somebody would have found out by now what type of memory it would support. Surely not DDR II, eh?

 

[Varun]

I think good PC3200 would be a nice way to go, but as far as I know there isn't any CAS 2 DDR 400 yet. I could easily be wrong on this of course.

Here is a link showing the Hammer architecture

So it seems it can support all DDR RAM, at least maybe. Higher end stuff is more likely than PC1600. Also, looks like AMD will have their own chipset again, and hopefully they will market it and support it. I've got a Via now but I'd like to see AMD make a good platform for their processors.

 

[Ilmater]

No offense to you, of course, because at least you admit it. But that's exactly what the Pabster's site claims:
"While Intel won't be offically making the switch to DDR333 until this fall, this memory type has already become the standard in AMD systems. Today, you can also get modules for operation in the fast CL2 mode, and this is something that might not happen with DDR400 four months."
For a guy posting to a forum, how are you supposed to know. But for a review site, that's kind of ridiculous.

A quick look at Corsair's site shows that they clearly have a CL2 stick in 256MB and 512MB. They've been on sale at Pricewatch.com for almost a month. Like I said, for a user, it's totally understandable; but for a review site, it's ridiculous. Bah! Half the time I hate THG, and the other half I love them.

Anyway, the RAM IS out there, it's just a matter of whether or not the Hammer will support it.

 

[Varun]

And it looks like it will support it, It's going to be another 3-4 months before we start to see the Hammer in action but I can't see why they would not support DDR 400. Regardless the DDR 400 can be used in place of the 333 anyways. I'm not too sure about DDR II, I just haven't found enough info on this yet to really know when it is going to be finnalized and in use. You'd have to assume the Hammer would work with that too, it may just need a different motherboard. AMD has been pretty good so far with no changing the entire system in one shot so I think you are good to get DDR 400 now and use it in your hammer board.

 

[Daikaiju]

Looking at the current state of DDR400 (IE. Garbage!) i would say that unless a standard format for it is created soon, it will be DDR333. As has previously been mentioned, it obvious that Hammer will be ok with all DDR types, but AMD will have to do a much better job of a DDR400 chipset than VIA did with the awful KT400. As far as i know, the FSB of either Hammer processor has yet to be announced, and since the Athlon will have a 166/333mhz FSB long before the Hammer comes along, it safe to assume it will at the very least have the same. If it's going to be higher, say at least 200/400, then clearly the somewhat farcical state of PC3200 has to sorted out first.

 

[microAmp]

Originally posted by: Daikaiju
Looking at the current state of DDR400 (IE. Garbage!) i would say that unless a standard format for it is created soon, it will be DDR333. As has previously been mentioned, it obvious that Hammer will be ok with all DDR types, but AMD will have to do a much better job of a DDR400 chipset than VIA did with the awful KT400. As far as i know, the FSB of either Hammer processor has yet to be announced, and since the Athlon will have a 166/333mhz FSB long before the Hammer comes along, it safe to assume it will at the very least have the same. If it's going to be higher, say at least 200/400, then clearly the somewhat farcical state of PC3200 has to sorted out first.

Correct on the DDR400 being garbage. I saw on THG, their KT400 small round up review of mobo's that the DDR400 RAM performed slower than the DDR333.

link

 

[andreasl]

AMD has clearly stated that Hammer will support PC1600, PC2100 and PC2700. Single channel in Clawhammer and dual channel in Sledgehammer. Whether it will unofficially support PC3200 is anyone's guess. They might include a multiplier for it but unless PC3200 has become a JEDEC standard until then, 100% compatibility is not guaranteed.

Oh and Hammer doesn't have a FSB in the traditional sense due to the integrated memory controller. The ondie link between the memory controller and core runs at core speed and is 64 bits wide (this info comes from the recent Hammer PDF from the HT site). Assuming a core clockspeed of 2GHz that is then 16GB/s of bandwidth = enough to handle whatever memory you throw at it for the next 2-3 years.

The "FSB" of the Hammer is really just the HT link between the CPU and the AGP/PCI-X bridge and it is also plenty fast enough (3.2GB/s in both directions for a combined cool 6.4GB/s). And this link will be as unimportant to performance as the present NB-SB links in current PC chipsets because it's plenty fast enough not to be a limiting factor. Only the presence of this link is the performance enhancer because the IO devices no longer have to fight with the DRAM for FSB bandwidth.

 

[Ilmater]

Originally posted by: Varun
And it looks like it will support it, It's going to be another 3-4 months before we start to see the Hammer in action but I can't see why they would not support DDR 400. Regardless the DDR 400 can be used in place of the 333 anyways. I'm not too sure about DDR II, I just haven't found enough info on this yet to really know when it is going to be finnalized and in use. You'd have to assume the Hammer would work with that too, it may just need a different motherboard.

That is not correct. Since the memory controller is integrated into the Hammer, then it will take a mobo upgrade AND a processor upgrade.

 

[microAmp]

Originally posted by: andreasl
AMD has clearly stated that Hammer will support PC1600, PC2100 and PC2700. Single channel in Clawhammer and dual channel in Sledgehammer. Whether it will unofficially support PC3200 is anyone's guess. They might include a multiplier for it but unless PC3200 has become a JEDEC standard until then, 100% compatibility is not guaranteed.

Oh and Hammer doesn't have a FSB in the traditional sense due to the integrated memory controller. The ondie link between the memory controller and core runs at core speed and is 64 bits wide (this info comes from the recent Hammer PDF from the HT site). Assuming a core clockspeed of 2GHz that is then 16GB/s of bandwidth = enough to handle whatever memory you throw at it for the next 2-3 years.

The "FSB" of the Hammer is really just the HT link between the CPU and the AGP/PCI-X bridge and it is also plenty fast enough (3.2GB/s in both directions for a combined cool 6.4GB/s). And this link will be as unimportant to performance as the present NB-SB links in current PC chipsets because it's plenty fast enough not to be a limiting factor. Only the presence of this link is the performance enhancer because the IO devices no longer have to fight with the DRAM for FSB bandwidth.

Thanks for the info.

Question though, since the memory controller is on the CPU and there is no northbridge for the memory chips, will o/c be possible? Or will there be a way to control the memory controller in the CPU through the BIOS.

 

[andreasl]

Originally posted by: motoamd

Originally posted by: andreasl
AMD has clearly stated that Hammer will support PC1600, PC2100 and PC2700. Single channel in Clawhammer and dual channel in Sledgehammer. Whether it will unofficially support PC3200 is anyone's guess. They might include a multiplier for it but unless PC3200 has become a JEDEC standard until then, 100% compatibility is not guaranteed.

Oh and Hammer doesn't have a FSB in the traditional sense due to the integrated memory controller. The ondie link between the memory controller and core runs at core speed and is 64 bits wide (this info comes from the recent Hammer PDF from the HT site). Assuming a core clockspeed of 2GHz that is then 16GB/s of bandwidth = enough to handle whatever memory you throw at it for the next 2-3 years.

The "FSB" of the Hammer is really just the HT link between the CPU and the AGP/PCI-X bridge and it is also plenty fast enough (3.2GB/s in both directions for a combined cool 6.4GB/s). And this link will be as unimportant to performance as the present NB-SB links in current PC chipsets because it's plenty fast enough not to be a limiting factor. Only the presence of this link is the performance enhancer because the IO devices no longer have to fight with the DRAM for FSB bandwidth.

Thanks for the info.

Question though, since the memory controller is on the CPU and there is no northbridge for the memory chips, will o/c be possible? Or will there be a way to control the memory controller in the CPU through the BIOS.

AMD hasn't disclosed any clockspeeds or anything related to that yet. But logic tells me there has to be a base clock going into the CPU and the support chipsets somewhere. And this clock should be in the range between 100-200MHz. It's then used to create all other clocks by multipliers and so on. Some people have suggested the HT clock of 400Mhz would be the system clock but I doubt that because the chipsets don't run at 400MHz but at the 100-166MHz range and so they would need clock dividers which would just complicate things more than necessary. Anyway like motherboard makers today allow modification of the system clock beyond the manufacturer specs I don't think it's too far fetched to think that they will allow this for Hammer motherboards too. Time will tell.