Bulldozer, new socket?

griff30

griff30

Supreme [H]ardness
Joined
Jul 15, 2000
Messages
7,212
I'm happy AMD made a very overclockable CPU with the x6 but I'm wondering if they will be using AM3 or AM3+ as the socket for the Bulldozer which is what Im waiting for.
If so I may build a AM3 system in hopes that the new Architecture will be backword compatable with the AM3 socket.
Anyone read anything about AMD's next year CPU socket?
Thanks
 
From what i read so far it will be new socket with three or quad channel memory but it will also work with am3 mobos at the cost of less memory bandwidth.
 
Michaelius said:
From what i read so far it will be new socket with three or quad channel memory but it will also work with am3 mobos at the cost of less memory bandwidth.
Click to expand...

I know thats true for the server part. Never heard of that for the consumer part.
 
my assumption is that it will be "AM3+", and work like AM2/AM2+....backward compatible(probably no power problems, since 140W is pretty much the standard)....AMD probably wont support Bulldoze on the 700 series chipset, again my assumption


in all honesty it is much too early to tell
 
Michaelius said:
From what i read so far it will be new socket with three or quad channel memory but it will also work with am3 mobos at the cost of less memory bandwidth.
Click to expand...

How? You are not going to be able to physically fit a 1400+ pin cpu in a 938 pin socket. To have triple channel or quad channel there will have to be more pins. Each channel of memory takes over 200 pins.
 
drescherjm said:
How? You are not going to be able to physically fit a 1400+ pin cpu in a 938 pin socket. To have triple channel or quad channel there will have to be more pins. Each channel of memory takes over 200 pins.
Click to expand...
AMD could theoretically still do quad channel memory with socket AM3... A lot of those 1400+ pins on the Server grade cpu's is for more than 4 memory slots per cpu and for the additional hypertransport links for multi-socket systems....neither of those is a requirement for consumer level motherboards.

There are currently 4 memory slots on most consumer AMD boards now. 2 memory slots for each channel of RAM. All they would have to do is make each slot an individual channel. 4 slots, 4 channels. Granted this will limit memory capacity, but that won't be much of an issue on consumer and enthusiasts boards.
 
There are currently 4 memory slots on most consumer AMD boards now. 2 memory slots for each channel of RAM. All they would have to do is make each slot an individual channel. 4 slots, 4 channels. Granted this will limit memory capacity, but that won't be much of an issue on consumer and enthusiasts boards.
Click to expand...

There are 2 pairs of 2 dimms that are in parallel, you can not break that without adding pins.
 
Talking out of my ass here, but isn't it the connections on the motherboard that make the slots on each channel parallel? If you build the new CPU so that it can support 4x individual channels or 2x dual-dimm channels then it could drop into a present-day AM3 board and operate but still offer quad-channel if the motherboard supports it.

I can see it going either way. It's been a loooong time since AMD released something that required a completely new platform with 0 backwards compatibility. I wouldn't begrudge them the change if that's what it takes to move past dual-channel memory.
 
but isn't it the connections on the motherboard that make the slots on each channel parallel?
Click to expand...

Yes. There are 2 sets of 240 pins that are in parallel. And that parallel connection is on the motherboard side. Each channel connects to the cpu not each dimm.

If you build the new CPU so that it can support 4x individual channels or 2x dual-dimm channels then it could drop into a present-day AM3 board and operate but still offer quad-channel if the motherboard supports it.
Click to expand...

No. This would require around 480 more pins (probably a little lower than that since the cpu does not power the ram and power can be shared between all dimms).
 
Last edited:
drescherjm said:
There are 2 pairs of 2 dimms that are in parallel, you can not break that without adding pins.
Click to expand...
interesting...
I'm assuming by what your saying that each channel of RAM can share the same motherboard traces? In other words 2 slots share the exact same mother board traces, and the logic in the CPU determines how to address them?

I took a look at a dead AM2+ board I have here, and almost all of the pins from slot 1 share a motherboard trace with the pins on slot 3. Simply put, one pin from the cpu goes to 2 pins, each of which were on different ram slots.

Using your argument, 240pins for DDR2/3 multiplied by 4 slots (each slot being a channel) equals 960 pins by itself. So I do believe you were right on this one.

Assuming 4 slots of DDR3 implementing quad channel as each slot is a single channel, and assuming that the cpu needs roughly 438 pins for other uses (socket AM3= 938, subtract 480 pins for ram), then the Bulldozer socket would need almost 1400 pins as was stated earlier in the thread.

Therefore, the only way a consumer level Bulldozer is going to work in an AM3 socket is if they only implement dual channel and save quad channel for server and workstation where its truly needed.
 
I'm assuming by what your saying that each channel of RAM can share the same motherboard traces?
Click to expand...

Pretty much. I believe there are a few address pins that will not be shared and also the power pins for the dimm do not connect to the cpu so the 240 number per channel is a little high.
 
They're probably going to make two new sockets, one for enthusiasts and one for regular desktop users. Probably AM3+ socket with backwards compatibility and dual-channel memory, and a new socket with quad-channel memory. Either way, the new chips will be based on the Bulldozer platform. Eventually, they'll migrate everything over to the new socket with quad-channel memory, but that's probably going to be at least 3-4 years down the road. They may even make the new quad-channel memory motherboards backwards compatible with current AM3 processors, I can think of several ways they might make that happen.

Just speculating.
 
What it all boils down to is that none of us know. AMD has been very tight lipped with any information regarding Bulldozer. Even the core diagrams out there are only speculations from someone officially outside of AMD, though I do believe he's on the money. He's from Dresden, Germany which is where the chips have been historically fabbed. Since Bulldozer is a completely different architecture from K8/K10/K10.5, I believe it would be best to start from scratch.
 
I also believe that there will be a quad and dual channel version. However I personally do not believe it will work on existing chipsets. The new platform of APUs allowing great numbers of cores per CPU and other new tech is going to make supporting older hardware too costly and limiting. Also the nightmare of having some reviewer using it on some older AM2+ mobo with DDR2 memory.

The new 45nm stepping is going to give us amazing duals tris quads and of course X6 cores for the rest of the year and beyond. AM2 to AM3 is set.

If they are to beat Intel they have to get serious...
 
Hmm maybe they could bring two versions of chip like socket 754 vs 939 days ? Anyway i see a lot of pissed of people if Bulldozer doesn't work on Am3 mobos bacause at the moment upgrade path is one of the very few aces left in amd deck.
 
They aren't going to make a die with more than 2 memory channels. The server part will be an MCM with 4 channels like the current Magny Cours and will be a drop in replacement on existing socket G34 systems.

I dont work at AMD or have any inside knowledge but AMD isn't going to build something as expensive as what you guys are speculating and they wont alienate existing G34 owners. Especially since even the i7 barely increases performance for a third channel.

I'm crossing my fingers on AM3 but any issues there are more likely to be 32nm power requirement related than anything else. By necessity this part will use HT and dual channel DDR3
 
The big problem is Intel will have quad channel in their enthusiast lineup. Also if bulldozer is an 8 core/4 module chip its likely to need more bandwidth than dual channel ddr3.
 
what you guys are speculating and they wont alienate existing G34 owners
Click to expand...

I would hope the new platform would be significantly faster than G34 otherwise all hopes for an AMD leapfrog of Intel are out the window.
 
Right now AMD has 2 top-end sockets. AM3 and G34. Socket F and AM2+ are going away. AMD is also releasing a second server socket that only supports up to 2 CPUs. C32 I think. If the desktop Bulldozer part uses a new socket that is not Backwards compatible with AM3, then that will probably be the only new socket. G34/C32 were designed with Bulldozer in mind and they have been clear that Bulldozer server parts will drop into G34 motherboards. I expect Bulldozer server to be a monolithic die with 4 memory channels, but I don't know that for sure.

I wouldn't take a bet either way on Bulldozer being backwards compatible at least with 8** series chipsets. If they can increase their memory channels to 4x and stay within 938 pins, kudos. If they sacrifice performance to maintain backwards compatibility then I think that's the wrong move. When i bought my current Mobo(790FX) I was hoping for a 6-core CPU but I never expected it to last to a whole new architecture.
 
flogge said:
Right now AMD has 2 top-end sockets. AM3 and G34. Socket F and AM2+ are going away.

I wouldn't take a bet either way on Bulldozer being backwards compatible at least with 8** series chipsets. If they can increase their memory channels to 4x and stay within 938 pins, kudos. If they sacrifice performance to maintain backwards compatibility then I think that's the wrong move. When i bought my current Mobo(790FX) I was hoping for a 6-core CPU but I never expected it to last to a whole new architecture.
Click to expand...
First off, I agree that AM2+ is definitely a dying breed. I wholeheartedly agree with the bolded statement as well. If AMD wants to be known for top-of-the-line performance next time around, they can't go sacrificing performance for backwards compatibility. Of course it would still be nice to have the next socket type compatible with 7XX chipsets since you can currently get a decent mobo for chump change.
 
Thanks for the replies.
I think I will wait for bulldozer and uber membandwidth that comes with it.
 
With all the changes with bulldozer the Phenom III or whatever they call it needs to do away with AM3. Yes if it only maintains dual channel I guess it might be ok but a new socket means new features. Also how are they going to have on CPU graphics without more pins?
 
Zachstar said:
With all the changes with bulldozer the Phenom III or whatever they call it needs to do away with AM3. Yes if it only maintains dual channel I guess it might be ok but a new socket means new features. Also how are they going to have on CPU graphics without more pins?
Click to expand...

I forgot about the GPU on chip..
Revolutionary and needs at least a new MB and socket,
I do with they would do an SMP version.
 
bulldozer will not come with GPU on the chip, at least not from the amd road map, the first fusion part will be a phenom II core (2/3/4?) with a gpu, then bulldozer will get it later on.
 
That sounds far more like the difference between desktop and server chips.

Of course with server you dont want the gpu on there. Waste of money and heat.

But with desktop it sounds like Phenom III with a new socket in my opinion.

Edit: I believe this is what you are talking about http://www.anandtech.com/show/2871

Why on earth would AMD launch a new socket to support APUs with Phenom II but not with Bulldozer. Dont get me wrong if its cheap I will get it but common!
 
flogge said:
Right now AMD has 2 top-end sockets. AM3 and G34. Socket F and AM2+ are going away. AMD is also releasing a second server socket that only supports up to 2 CPUs. C32 I think. If the desktop Bulldozer part uses a new socket that is not Backwards compatible with AM3, then that will probably be the only new socket. G34/C32 were designed with Bulldozer in mind and they have been clear that Bulldozer server parts will drop into G34 motherboards. I expect Bulldozer server to be a monolithic die with 4 memory channels, but I don't know that for sure.
Click to expand...

Here's what I think AMD should do...

Make Bulldozer in several socket configurations.

Socket AM3:
-Budget series, similar to how socket 754 was to socket 939
-drop AM2+ backwards compatibility
-compatible with current 8 series chipsets with bios updates
-Dual channel only to keep within socket AM3 pin requirements
-No On-Die graphics (Fusion) to keep within socket AM3 pin requirements
-Do a limited run (1 year production maybe?) of atleast 4 parts: 1 quad core Black Edition, 1 quad core non Black Edition with slower clocks, 1 Dual core Black Edition, 1 Dual core non Black Edition with slower clocks. Don't bother making a Tri-core, don't want to oversaturate this piece of the market too much.
-Highest priced Black Edition Quad would be around $150-$200

Socket C32:
-Full blown Bulldozer for Enthusiasts, Workstations, and 1P and 2P servers,
-Low End parts with on-die graphics would start shipping just as AM3 models begin EOL
-Highest speed enthusiast part at launch faster than fastest AM3 part either through higher clock frequencies or sheer number of cores.

Socket G34:
-Full blown Bulldozer for high-end servers
 
CaptNumbNutz said:
of atleast 4 parts: 1 quad core Black Edition, 1 quad core non Black Edition with slower clocks, 1 Dual core Black Edition, 1 Dual core non Black Edition with slower clocks. Don't bother making a Tri-core, don't want to oversaturate this piece of the market too much.
Click to expand...

Actualy those won't be called cores anymore ;)

http://www.anandtech.com/show/2881

It kinda looks like similar idea to what happened in GPU few years ago with split into many specialized units.
 
I kind of like the idea. Tho if they are intending to launch Phenom II 32nm with on die graphics parts I greatly worry about them flooding the market and confusing reviews could result.

They talk about "mainstream" as these new Phenom IIs however people having to buy a new mobo while top of the link folks get to ride easy on AM3 sounds like fast track to disappointed customers. Tho AMD can make it easier by having low prices for the now graphicsless northbridge and ensure it retains lots of PCI express lanes.
 
You must log in or register to reply here.
Back
Top