[Armin]

Hello everyone,

As the title suggest I am trying to buy a small workstation. I am mainly
interested in HP products, because they seem more experienced in the field.

However I have a couple of questions:
1- what is the main difference between i7 and Xeon proc's? Moreover, there
are many models available models as far as Xeon is concerned? which one
is suited for numerical work?

2- There is a new product (HP Z1 all in one station):
http://www.hp.com/united-states/camp...l#.T2YN7-KimRI
Has anyone any thoughts on this, e.g. if it is a better choice than a tower Z800?

3- For numerical work(this being a CFD website afterall ), should I spend more money on memory or CPU?

4- It would be nice to also hear from people, who have actually done something like this. And if possible it would be nice to know which
config. they are using right now, and if they are satisfied with it.

Any response would be highly appreciated and responded with a warm
thank you!

[abdul099]

1. i7 CPU's are intended for use in single socket systems. Xeon's are usually derived from desktop CPU's but designed for multi socket systems. In the most cases, they are slower (on a 1-1 comparison of a single core) but more reliable (due to ECC RAM). There's one exception: Some Xeon's designed for single socket systems are nearly exactly the same as the i7 series, therefore they perform quite the same - at least in theory.
As far as I know, there are currently no Xeon's with a Sandy Bridge architecture available. Sandy Bridge would be great for a single socket system since they've got four memory channels and seem to perform very well.
The next choice are the some Westermere Xeon's with some of the higher X-numbers.
But none of them is available for the HP Z1.

2. Don't know much about HP workstations. At work I'm happy with a Dell workstation. But just looking at the specs tells me, the Z1 can't catch up with a "serious" workstation.

3. Depends on your problem. You should purchase enough memory for your problem size. Having not enough memory causes your machine to swap and slows your process down enough to get you thinking "Why the f... didn't I buy more memory?"
But as soon as you've got enough memory, it doesn't help at all to increase the amount of memory, so I would go for a faster CPU to give a extra boost on meshing and solving.
Consider you might need more memory in the future since your usual problem size might increase or you want to work on two cases at the same time.

4. I got just a desktop machine at home for a quite simple reason: The price.
I don't solve any huge cases at home, so I just bought a 16GB machine with a Phenom II CPU (shame on me, it's incredible slow).
Anyway, the specs of the Z1 are low enough to be beaten by a (less expensive) desktop. There are quite fast Sandy Bridge E cpu's and some mainboards can handle up to 64GB memory, that should be more than enough. So why spending a lot of money for a workstation when a cheaper machine can do the same job? I assume, you don't solve any huge cases since the Z1 doesn't bring along enough power to do so.
You can get a small cluster, thrown together from machines of the shelf, for the price of a single, less powerful workstation.
The only mistake I did when I bought my machine at home was to go for a AMD cpu - but it was cheap.

[Armin]

thanks a bunch for the detailed answer abdul099.
a few points though: Intel Xeon E3-1280 ships with a sandy bridge as far as I know... doesn't it?

The main reason I am considering Z1 is the cool inside design. It seems incredibly low on weight and highly customizable (and frankly it looks cool )

I compared it to other workstations in from HP and considering the price, it seems to give good performance. But my Judgement in the field of proc's is rather clouded. Isn't a quad core Xeon (3.5 MHz) with 16 G DDR3 enough for CFD (say a finite difference method with 500000 grid points in fortran) ? Or am I way of chart?

After all if I am correct, sandy bridge proc's are technologically newer than Nahelem based proc's. And many of the todays supercomputers use Nahelem ( e.g. Jugene-Germany) So it should give me better performance right?

I just configured a Dell™ Precision™ T1600 with the same spec and ended up with
a higher price (Z1: approx. 1200 Euros and Dell:2000 ) Or is it something here that I am not seeing??


Again thank you for your kind answer abdul099.

[gricko]

Hello,

I would like to attach a simillar question.

What do you think about the following configuration to run Ansys 13 (cfx) in beginner level... For my diploma I have to do something like the 17th tutorial. Air dispersing in a mixing wessel.

The configuration of the computer would be:

2x Intel Xeon QuadCore 2.83 GHz (E5440), L2 cache 12 MB, 8 GB (max. 128 GB), 73 GB GB SAS, LSI SAS1068-IR, RAID Controller (RAID SAS 0/1/10, RAID SATA 0/5/10), DVD, USB 2.0 x 7 (2+5), COM, PS/2 x 2, LAN 10/100/1000, NVIDIA Quadro FX3700 (512 MB, DVI x2, S-video)

It is a used HP xw8600 workstation (3,5 years old Leasing Machine)...
For the price of 680€

Many thanks in advance!
Darko

[abdul099]

Armin, you're right. The new Xeon E-Series are based on Sandy Bridge - but not yet available. I just checked with my favourite dealer, you can just pre-order them there.
And a few weeks ago, I didn't find any multi-socket mainboard for socket 2011 while they are available since months for single socket systems (i7). That's why I wrote, Xeon CPU's based on Sandy Bridge are not yet available. I apologise for that.

You're right that Sandy Bridge is much newer than Nehalem. Also Sandy Bridge has the potential to perform much better. But there's a simple reason why all recent supercomputers run on Nehalem right now: The only Sandy Bridge CPU's available right now (or at least when the last supercomputer was build) are core i3 - i7 and they are designed for single socket systems. That will change for sure when Xeon E5 and E7 are available since they've got much more memory bandwidth.

So as long as you stick to a single socket system, there's no reason to prefer Nehalem, Sandy Bridge is (usually) better.

You're also right, 16GB are more than just sufficient for a 500 000 cells case. A 8GB machine would also be more than just sufficient. And a quad core is also fine for this low element count.
Of course you can purchase whatever you want, but you can get a desktop machine with a faster cpu and faster memory for less money. With this low specs, there's NO reason for me to stick to a workstation. That would be different when you would go for a dual-socket system with 128GB memory. But you don't need that for a 500 000 elements case. You can even solve it on a laptop!

Anyway I wouldn't purchase a Z1 for a quite simple reason (apart from the price): The Xeon E3-series offers only two memory channels which is crap for most CFD applications. The E5-series (or an core i7) is not available for the Z1

[evcelica]

Xeon E-5 sandy bridge-E are available, single and dual socket versions, along with motherboards. You probably cannot get them from Dell or HP though. You could either build your own computer, or find a different company who has these processors available in an off the shelf system.
How much do you plan on spending? How many cores will you be able to run? These are the main factors in determining what type of workstation(s) to get.

[Armin]

Hi Abdul,

Now I get what you mean,

Thanks a bunch for your pointers

[Armin]

Hi Erik,

I was planning to go as high as 4000 Euros (Everything included) at max. The data that I provided on the previous post (CFD simulations) are just a guess. They might be totally of the chart. My research in the field show that a dual socket system(each Quad-core - E5 series) with 16 GB should be more than enough. And as for your other question, the code that we has already been tested on a supercomputer and is able to run effectively on a dual socket system (four cores each).

Anyways I am not planning on buying the system right away, I am just doing research on alternatives, so E5 series might be out by the time I actually decided to buy the system.

Oh and an update: my project will probably also involve FEM, LBM and level set methods, so I think a higher spec is required.
second Update: I have recently found a shop in Germany, named "Rect shop", they also have a configurator. The prices are also reasonable in comparison to Dell or HP, has anyone hear of this one?

Thanks,
Armin

[DoHander]

Are you sure you can configure and purchase a HP system from Germany ? Your initial link is to HP US and they usually ship only in US. I know that because I've tried to buy a custom HP system from Canada and they've specifically request for US billing and shipping address.

A preconfigured HP system can be purchased from everywhere, not a configurable one apparently ...

[Armin]

Hi

Well technically you are right, BUT there are handlers in Germany who are willing to customise your HP workstation as long as your are tied to an institute of a company.