- Oct 20, 2005
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Topic title says it all. With the introduction of C2Q I can see where 16GB or 32GB would be extremely useful especially for running multiple VMs.
True today. 2 x 1GB DDR2 is pretty reasonable now; 4GB sticks will be reasonable in 18 months.Originally posted by: Roguestar
And 4x 4Gb sticks of DDR2 is going to bring down the house in terms of cost!
Will we see non-ECC, non-registered, non-buffered (i.e. desktop) DDR2 memory in the 4GB and 8GB per stick range?Originally posted by: Peter
More than two slots per channel would mandate Registered or Fully Buffered DIMMs, and that in turn forces you away from desktop class to server/workstation chipsets.
I'm assuming that the chipsets I mentioned in the second post provide such support. Is that a fair assumption?Originally posted by: Peter
Since it's the chip addressing that limits the DIMM size for a given chipset, you'll have to look at whether today's chipsets actually support chips that large.
Good point. I'm thinking 64-bit Windows Vista Business or Ultimate, both of which support up to 128GB RAM.Originally posted by: oldgeezzer
2^^32 allows only a little over 4 gig byte addressing. A lot of the "how much memory is enough" problem depends on the OS being used
LOL. That's exactly what I've got now: 3 x Athlon XP 2x00+ based machines along with a couple older workstations. I plan to assemble 3 (probably C2D upgradeable to C2Q) based machines in 2007. But a max of 8GB ain't going to cut it for any of those machines especially running a 64-bit OS.Originally posted by: severtki
Cheaper solution: Build several separate machines and use KVM switch or VNC server to control them. You could build yourself 3 or 4 cheap machines, each with 2 GB RAM for lots cheaper than outfitting a single quad-core machine with 8GB+ RAM.
Just a thought... probably not what you're looking for, but...
I wasn't aware of this; thanks for pointing it out. 64GB would satisfy my needs. Now if vendors would only implement even close to that.Originally posted by: Peter
Keep in mind that C2D's total address space is only 36-bit (64 GiB), Opterons currently use 40 (one Terabyte).
Frankly I'm not convinced that AMD, even with K8L, will be able to *convincingly* overtake C2* in 2007. I think AMD is going to be competitive and will be able to preserve their critical gains in the server space starting in the 2007H2. That doesn't help me; I need a solution starting in the first quarter of 2007 and C2* seems more than sufficient for my needs. Current overclocking convinces me that there's plenty of clock "headroom" in the C2* architecture.If you want to build something today that lets you upgrade next year or even later, then you should REALLY opt for an Opteron box - these have the RAM controllers on the CPU, which support large DIMMs, and also bring another pair of RAM controllers with every CPU socket ... and have a longevity plan that lets you put future CPUs into today's sockets for quite a while longer than Intel will let you.
Workstation class boards, dual sockets, ECC memory, ahhh... that's the rub. Too rich for my budget.So a dual-socket Opteron could get you started with one dual-core CPU and two DIMMs, and take you up to eight cores, four RAM channels and up to eight or sixteen DIMMs ... registered ECC DDR2 though.
Like, if you're worried about max RAM size, you might find this here quite nice
http://www.tyan.com/products/html/thunderh2000m.html
I've ruled out dual processor boxes (i.e. boxes with two CPU sockets) due to motherboard and memory costs. In addition, Anand's recent review of C2D vs. C2X vs. QFX doesn't show QFX in a good light for general computing (i.e. non-server) workloads.Originally posted by: Peter
Why still multiple CPUs? With Intel's northbridge centric approach, there's little point. With AMD, you have the choice - many cores working on one pair of RAM controllers, or many nodes, each with its local pair of RAM controllers. The latter is performing considerably better when you have tasks that work on separate datasets - as you would when you're running virtual machines - and of course lets you have more DIMMs overall. Also, you don't /have/ to populate both processors in a dual socket board. Buy one now, upgrade later - add a second dualcore CPU and another pair of DIMMs, or maybe even a quad CPU alongside the dual CPU you originally had, why not.
This is interesting speculation. Intel ruled for so long we've taken their arrogance for granted. Having spent 2002 through mid-2006 getting the stuffing kicked out of them seems to have had some positive consequences. C2* is a real *asskicking product line (certainly in the mobile and desktop markets) with real growth (i.e. performance) potential. This is not your father's Pentium4 with the Rambus memory mumbo-jumbo.There might be plenty of headroom in C2, but just look at the plans (and the historical backlog) to figure how far an Intel board bought /today/ is going to take you. Hint: Not too far.
It seems to me that performance of AMD's next generation is going to *try* to beat Intel's currrently shipping products. We know Intel's current architecture can ramp up to 4GHz range.; it's not clear if AMD's next generation will be able to do so. The current QFX offering for desktop-type tasks gets blown away by C2X. As for AMD's architecture after K8L, who knows...AMD in turn have clearly indicated that at least the next two generations of Opterons will fit the current socket.
On server platforms, I agree with you 100%. I'm not interested in building server-class boxes.As a side note, max RAM size with AMD's current CPUs appears to be 4 GiB per chip (should they ever be made) - that translates to 8 GiB per unbuffered DIMM, sixteen per registered DIMM. Four unbuffered DIMMs take you to 32 GiB on an AM2 desktop board, eight registered DIMMs on a workstation board take you up to 128 GiB ... per CPU node, 512 GiB total for four of them.
That's why AMD is selling their Opterons like hotcakes, despite C2D being a /really/ good processor. It's the scalability and the longevity of stuff bought today.
I agree that my requirement (i.e. motherboards that support >8GB) is traditionally considered to fall in the server-class hardware space. However with the widespread availability of 64-bit processors, multi-core processors, and 64-bit operating systems (Vista and any flavor of Linux) the traditional boundaries between desktop, workstation, and server class spaces are changing. I am trying to take advantage of that fact and yet stay within the desktop space. There's a premium to be paid in the workstation and server markets. I specifically don't want to pay that premium. And although I haven't mentioned my other requirements I can share with you that they fall solidly within the desktop space.Originally posted by: Peter
Let me make one thing clear: You ARE asking for a server-class box, and you're not going to get what you want from a desktop platform.
AMDs K8L/"Stars" class processors for the desktop are not due until 2007Q3. It's clear from this article that current motherboards will *not* be able to take full advantage of at least some of the capabilities of those processors. Why in the world would I invest in a platform (AM2) that requires me to wait 6-9 months (i.e. until 2007Q3) to discover if a new processor architecture can beat what Intel's been shipping since 2006Q3?Using a C2D on a desktop board might get you the nicer (I said that!) processor, but on a platform that is weaker than you want TODAY.
That's why I recommended doing the reverse: Use more of today's money for a mainboard architecture that gives you the platform headroom you need, and which coincidentally will let you use the next two future (!) generations of processors and more RAM than you'll ever want.
I'd be perfectly happy with a motherboard that takes 16GB RAM; 32GB would be better but *any* improvement over 8GB is better than nothing. I don't need the fastest/bestest/b*itchenest systems on the block. I'm looking for a platform that lets me move up from C2D-level of price/performance (my starting point in 2007Q1) to C2Q-level of performance sometime in late 2008 when, I expect, C2Q absolute processor prices will drop. C2*'s price/performance is looking pretty good today. We know the C2* performance can be pushed to the 4GHz level - people are overclocking today's motherboards to get that level. If folks at the various enthusiast sites can make it happen for a few hundred dollars I'm willing to bet that Intel can figure it out too.Ask yourself: In 2008, is 2006's C2Q on a desktop board, limited to 16GB RAM (at most!) still going to cut it? Besides, I wouldn't expect Intel to keep today's top-of-the-line offerings available until then. FSB change, chipset compatibility "issues", and off you go buy a new mainboard to your new CPU. That's how it's always been since the 486 days, and that's how it's going to continue as long as there is a front side bus/northbridge architecture.
I think server-class RAM is traditionally at least 25% more expensive than desktop RAM. Why should I spend 25% more and not get any benefit based on my needs.Reg ECC RAM isn't /that/ more expensive than /quality/ unbuffered, btw. Intel will make you buy Fully Buffered DIMMs next year, and these /are/ expensive.