Will the 64 GB of the x3755 of ram run with 400 Mhz or will it drop to 333 or even 266 MHz ?
I talked to our IBM rep and it looks like there's alot of interest in these products so I suspect I won't be getting my hands on one until October.
The LS20 blades took forever to get here. One great advatage of the LS21 over the LS20 is the extra DIMM slots - this is a real handicap of the LS20s since 4 Gig DIMMs don't come cheap.
The x3755 is able to drive up to 128GB of memory at 667Mhz.
The x3755 will be able to drive 4 DIMMS per CPU's at 667MHz (which is over the standard AMD specs). I suspect other AMD based systems vendor will have to drop to 533MHz when attaching 4 DIMMS per socket (need to check).
suspect other AMD based systems vendor will have to
(need to check).
That s not true, DDR2 Technology with 667MHz has a general limit of 4 DIMMs, so also other vendors (no I do not want to make advertisment) with 2 characters have a quad core offering , and on one socket you will have 8 DIMMS, if using 667MHz then you are able to attach 4 DIMMs (no we do not drop something) and if want populate every 8 DIMMs per socket[/b] then you drop to 533MHz[/b]!
This general limitation for DDR2 only 4 DIMMS, was among other things (lower pin count, Reads and writes simultaneously, higher memory speed) to go into serial technology FBDIMM you will today find in intelbased Servers.
my 2 cents
what can you say about the new hp dl 585 g2.
Is the following right:
HP DL585 G2 with 64 GB memory at 533MHz
HP DL585 G2 with 64 -128 GB memory at ???
Which memory dimms are available?
2 Gb Dimms
4 GB Dimms
8 GB Dimms
Sorry. That was a typo.
I should have read:
The x3755 will be able to drive 8 DIMMS per CPU's at 667MHz (which is over the standard AMD specs). I suspect other AMD based systems vendor will have to drop to 533MHz when attaching 8 DIMMS per socket (need to check).
And I stand behind this statement (that you confirmed) From the IBM page:
>The IBM System x3755 provides breakthrough performance for >applications that demand maximum memory availability. With IBM >Xcelerated Memory Technology, the x3755 will deliver up to 15% better >performance than competition resulting in the best price performance 4->socket server in the industry.
Xcelerated Memory Technology is a patent-pending solution from our R&D.
The IBM performance lab is about to write a detailed technical paper on this topic among other IBM uiniquenesses for the x3755 such as the CPU Pass Thru Card (more to come on this). I just hope that this document will not be IBM confidential so that I can send it to your e-mail address email@example.com. Oh if it is IBM confidential I could send it to you anyway but than I have to kill you ..... your call. (come on ... take it easy ... I am just kidding my friend).
128GB populated 4 GB on 8 DIMMs per socket with 533Mhz
64GB populated 4GB on 4 DIMMs per socket with 667MHz
1 GB REG PC2-5300 (2 x 512 MB) single rank
2 GB REG PC2-5300 (2 x 1 GB) single rank
4 GB REG PC2-5300 (2 x 2 GB) dual rank
8 GB REG PC2-5300 (2 x 4GB) dual rank
DL585G2 refreshed with our SAS Controllers (P400, P600), ILO2 , Multifuncton Nics etc etc
No do not send proprietary materiels on my mailbox there is a sticker "no advertisments to my address" If you want, send it to me
You are lucky.
I won't have to kill you (this time):
The interesting part is:
The server generally follows a standard four-socket Opteron processor design,3 but with
improvements in key areas that will be mentioned throughout this paper. The four processors are
connected together by HyperTransport links in a ring topology. Each processor may have up to
eight DIMMs on two memory channels. One key improvement is that all 32 DIMMs operate at
667 MHz. AMD system development guidelines specify that 533 MHz memory be used for
reasons of signal timing when connecting more than two DIMMs per channel. IBM developers
have discovered a way to maintain timing and electrical integrity while using four DIMMs of the
faster memory. This innovation allows the x3755 to use high-speed memory even in very large
memory configurations (configurations above 64GB), and less expensive memory in
configurations up to 64GB without significant loss of performance.
Another key innovation is the pass-through module. Figure 1(A) shows an x3755 configured with
four processors. Each pair of processors in opposite corners of the system is separated by two
hops; that is, in order to communicate, every message must traverse two coherent HyperTransport
(cHT) links. If the processor in the upper-left position were removed, processors in the lower-left
and upper-right positions would form a line rather than a ring. More importantly they would still
be separated by two hops. As shown in Figure 1(B), IBM provides a pass-through module that can
be inserted into the system in place of the missing processor to change the system topology from a line back to a ring. It will be shown in a later section (Section 2.6) that this configuration has
significant benefits to memory performance.
P.S. I haven't read it all yet either
Do you have any information on how the x3755 compares to the LS41 as well as comparison to the x3850? (intel)
thanx for this info
>Do you have any information on how the x3755 compares to the LS41 as >well as comparison to the x3850? (intel)
There is a similar paper for the LS21 that you can look at. The LS41 is basically an LS21 with an expansion device (basically another sort of LS21). Consider that I am still trying to get up to speed with these new announcements (too much stuff going on I can't really cope with all of them) but the LS21/41 "only" have 4 DIMMS per processor so it doesn't use the same Xcelerated Memory Technology we can use on the 3755 (with 8 DIMMS per processor). Also the LS21/41 do not support the CPU PassThrough card.
As per the Intel Vs AMD ........ you certainly don't want me to get into this religious mess. Simply put we use a customer chipset in the 3850 that makes it faster than any other 4-way Intel based system. This is kind of agreed by the whole technical community at this point (I think). I also think that with these uniqueness we are well positioned to say that the x3755 is better than any other "commodity" 4-way AMD system in the market (that's my speculation looking at the base technology building blocks ... keep it with a grain of salt and consider I am an IBMer ... ).
As per who's faster ? the x3755 or the x3850 ..... I would say it depends on the workload you are running......
A Good read! Is there anybody running ESX on the 3755 or is it still too new. I don't see it on the HCL as yet ...
It should be listed with the 3.0.1 but these things moves quickly in and out.... take it with a grain of salt.
BTW where did you see that it's supported for for ESX 3 ? I usually look at either the HCL or the Serverproven web site (the IBM compatibility site for xseries/blades) and it's not there:
There just too many sites reporting inconsistent information ......