New PC: biggest bang for the buck?

[Nocturnal]

Hi,

I'm considering building a new PC. It'll be a general purpose machine but of course I'll spend lots of time doing astro work on it too. I know PI uses multi threading so I'm getting a quad core CPU. Now the choice is between an i7 920 and one of the older quad cores. I suppose I should consider the Phenom series but I'm an Intel guy so that'll probably be it.

Now the i7 runs circles around other processors when it comes to memory throughput since we work with large amounts of data this seems important but is it? Could it be that many processes work on chunks of data that fit in cache so that memory bandwidth isn't the bottleneck?

Clearly I could simply build the fastest machine I can afford but I'd rather optimize things a little and spend money where it matters. Are there plans to use GPU acceleration? I've read a bit about CUDA but I'm not sure it's available cross platform.

The machine will most likely run 64 bit Vista. I'm not sure yet about the disk config. I realize that PI likes to have multiple drives for swap files. I don't think I'll accommodate that right away but use fast SATA drives and RAID for general speed and data protection of all applications. I can always add a drive later. Spreading out the 'investment' keeps prying eyes (wife) at ease you know

[Juan Conejero]

Hi Sander,

Personally I'd go for the i7.

Now the i7 runs circles around other processors when it comes to memory throughput since we work with large amounts of data this seems important but is it? Could it be that many processes work on chunks of data that fit in cache so that memory bandwidth isn't the bottleneck?

Of course throughput counts, but much more important is to have a *lot* of RAM. I'd consider 8 GB as a minimum. I recommend 16 GB. With a huge RAM everything runs faster (for example, you can accumulate many processing steps on previews) and you can do much more complex things (f.e. large wavelet transforms, especially HDRWT).

Are there plans to use GPU acceleration? I've read a bit about CUDA but I'm not sure it's available cross platform.

My advice is: buy an nVidia graphics card

Not in the short term, but PixInsight will use GPU acceleration via CUDA. Hopefully this year we'll have some core routines well implemented through CUDA. Convolutions and FFTs are the main initial candidates. Then depending on how things evolve we'll implement more sophisticated algorithms.

CUDA is cross platform. There are excellent implementations for Linux/UNIX, OS X and Windows. I have already studied some CUDA example code, and Oriol is also working on this.

My main problem now is that I have to update my main Linux workstation to install a CUDA-enabled video driver, which implies a recompilation of my Linux kernel, along with several key packages (VMware), monster backup copies, etc. This is stopping me because right now I need a fully operational machine all the time, and these changes would leave me out-of-business for several days. As soon as I can afford a full software update, I'll begin working on a port of some PCL routines with CUDA. I'll keep you informed.

The machine will most likely run 64 bit Vista.

It won't deserve that Seriously, you'll really hate Vista. I'd consider waiting for Win7, and use XP in the meanwhile. Or, much better, why not install a good Linux distribution instead?

I'm not sure yet about the disk config. I realize that PI likes to have multiple drives for swap files. I don't think I'll accommodate that right away but use fast SATA drives and RAID for general speed and data protection of all applications.

I use RAID 1 for the sake of security on all Linux workstations. RAID 5 and RAID 10 are good choices of course, but they need more drives, and nothing is more secure than a simple RAID 1.

Use a good software RAID implementation. This is also a good reason to use Linux Beware of mainboard RAID utilities; they are actually software RAID implementations that use comparatively slow processors, even the best ones, and if your motherboard crashes, you may have serious trouble to restore your drives due to proprietary RAID software. If you cannot afford a server-level dedicated RAID card, use software raid. Your i7 processor can perform all necessary RAID operations much faster than a mainboard based RAID. For example, I have two 750 GB SATA drives configured as RAID 1 with mdadm on Linux. I've never seen a processor load above 1%, even during intensive disk I/O operations. With this configuration, I have a consistent write speed of about 475 MB per second, and around 1100 MB/s for reading.

Buy two or three cheap, relatively small SATA drives with a good cache size, and use them only as swap storage drives. PI will perform undo/redo disk operations almost as if they'd happen in RAM

Spreading out the 'investment' keeps prying eyes (wife) at ease you know

Oh yes, of course. And you can invest more with a fraction of the total "pain"

Good luck with your new machine.

[OriolLehmkuhl]

Not in the short term, but PixInsight will use GPU acceleration via CUDA. Hopefully this year we'll have some core routines well implemented through CUDA. Convolutions and FFTs are the main initial candidates. Then depending on how things evolve we'll implement more sophisticated algorithms.

CUDA is cross platform. There are excellent implementations for Linux/UNIX, OS X and Windows. I have already studied some CUDA example code, and Oriol is also working on this.

Indeed , I have been done some test with onedimensional convolutions and its a must have for PI : it seems that is better for you the nVidia card

Regards,

[Nocturnal]

Very cool, thanks for the advise. I may move my Radeon 3850 from the old PC to this one for now and upgrade to a decent nVidia card when CUDA code for PI becomes available. Right now ATI is really spanking nVidia in the perf/$ department so I don't think it's the right time to get one.

As for the Vista bit, I know it's a shock but PI is not the only thing I run on my PC. I know, I know, I can hear you gasp I use DSS for stacking and lots of other software for other purposes. So I might get a copy of XP64 if I can get it but it sounds like Vista will get a free upgrade to windows7 when it comes out.

The RAM thing, yeah, 16 GB would be nice but I don't have *that* many images to deal with. I'll start with 6 (3 x 2) and see how things go.

[bitli]

Thanks for the information, this will eventually be helpful to me.

Currently I run PixInsight on a machine with a Dual Core E2180 @2GHz and 2GB of memory (800MHz).
The screen is a 22" 1680x1050.

This is less than the minumum requirement (it happens to be the cheapest system one could buy around Christmas, originally for my wife to read mail and internet).

In spite of that I found that Pixinsight runs OK, or a beginning user , as long as I limit the size and number of images open and have some patience. The current limitation is my skills, not the performance of the computer.

I almost give up downloading the trial version when seeing the official requirements. Fortunately I tested it and found it good enough to buy it. So readers that have a not very powerfull computer (mine seems to be near the lowest usable end), please do not hesitate to dowload the trial version PixInsight and see if you can make useful work with it in your configuration. You may find it useful enought to use (while saving for a more powerful computer).

bitli

[Nocturnal]

I haven't seen the official requirements but judging from Juan's post above I think there's a slight disconnect between what people do and what Juan *thinks* they do Not everyone is a professional astronomer who needs 20 SLT11K images open at a time. My computer is probably about as fast as yours (Dual Core E processors are faster than the P4D but my clock speed is higher) and it works fine with my modest 3K by 2K 32 bit color images.

As near as I can tell PI performance is much better than other software that's out there. For all kinds of reasons I'm sure but one is the multi core support. MaximIM, AIP4WIN, CCDStack and probably others don't do that. I know Craig is working on it for Nebulosity 2 and CCDStack has it planned but I read that MaximIM won't have it for a while. AIP4WIN probably never will because it's a VB6 app. New Photoshop versions apparently are multi core optimized.

The only thing I notice now and then is 'stickyness' in the histogram sliders and when I move DBE samples around.

My current computer would be sufficient for a while longer but it's time for an upgrade and so I wanted to know where the best bang/buck is.

[Simon Hicks]

Up until about a month ago I was using a 2GHz, single core, 1.25Gb RAM laptop on all my 3k x 2k x 32bit images. It worked slow, but it worked fine all the same.

Then the screen started to come away from the base...yippee...excuse to get a new laptop. I now have a 2.4GHz, dual core, 3Gb RAM laptop. Still pretty basic, but the increase in PI speed is fantastic.

I now use ACDNR with much improved results, simply because I can be bothered to fine tune the parameters....which took hours before (well tens of minutes).

So the Previews, and dragging Previews to make new small Parents is critical to anything I do.

I wonder what PI would be like if I had Juan's computer!  :lol:

Cheers
              Simon

[Nocturnal]

I've run PI with success on my 1.6G dual core centrino laptop with 3G RAM as well.

I think Juan should keep an entry level computer around just to remain grounded with his users. Perhaps the Mac takes care of that, I don't know how beefy it is. Not many people have a dual Xeon server class machine under their desk after all

[Juan Conejero]

A couple weeks ago I made a few photos of my workstation during some maintenance work to install a pair of new SAS drives. I think you'll probably be interested in taking a look at the machine where PixInsight is being cooked

http://forum-images.pixinsight.com/legacy/workstation-0902/01.jpg

I built this machine during May and June 2008. The motherboard is an ASUS DSEB-DG/SAS with two Intel Xeon E5420 processors (eight cores) and 16 GB of RAM installed (8 x 2GB Kingston FB-DIMM 800 MHz FSB modules).

Here you can see a closer view:

http://forum-images.pixinsight.com/legacy/workstation-0902/02.jpg

The graphics card isn't anything very special: a PNY nVidia Quadro FX 570 (some dust doesn't hurt, as you can see ). This machine has two 750 GB Western Digital SATA disks (server class drives) configured as a RAID 1 set. Along with these drives, I usually have two 160 GB SATA drives for swap file storage. Here I was replacing them with two new SAS drives. The case is an Antec P190 with dual power supply (1200 W total power), which I highly recommend.

Of course, this machine runs a 64-bit Linux operating system (Fedora 8, about to be replaced with Fedora 10). On this computer I run Windows Vista x64, Windows XP SP3 x86 and two Linux distributions on virtual machines under VMware.

The main monitor is a 24-inch DELL LCD. Here is a general view of the machine running my favorite image processing application

http://forum-images.pixinsight.com/legacy/workstation-0902/03.jpg

My other workhorse is a Mac Pro with 8 GB of RAM, which I mainly control from the Linux workstation via ssh. I'm about to install a second nVidia graphics card on this Mac to play with CUDA on OS X

[Juan Conejero]

I think Juan should keep an entry level computer around just to remain grounded with his users.

I have one It's a Pentium IV HT at 2.66 GHz with 2 GB of RAM. I must say that PixInsight runs fine on this machine under Windows XP. This is the machine where I wrote the PixInsight LE application.

I still have a Pentium II machine with 256 MB. On this machine I wrote some really old code which had some success, many years ago (the SGBNR noise reduction application). This computer still works perfectly. I built it in 1997, if I remember well.

And to complete my personal Jurassic park, I still have an IBM AT (compatible) with a nice 20 MB hard drive and a 5.25' floppy drive

As you can see, I am a bit sentimental regarding my old machines

[Nocturnal]

I don't really throw them away either although I tend to replace the guts and leave the case and whatever else I can re-use in place. So I have a box full of motherboards and other parts all the way back to a P2 of some sort. I don't think I ever owned a Pentium 1. My first PC was a 8088 based XT (Sinclair ZX-81 and C= 64 before that but those weren't PCs) and then I skipped PCs for a while.

[C. Sonnenstein]

The motherboard is an ASUS DSEB-DG/SAS with two Intel Xeon E5420 processors (eight cores) and 16 GB of RAM installed (8 x 2GB Kingston FB-DIMM 800 MHz FSB modules).

Absolutely

[David Serrano]

Just made this thread sticky since I think it may be of special interest to everybody. I'd also like to encourage people to post their hardware configurations in order to build a mini database of recommended/best hardware equipment.

If the OP doesn't mind, of course .

[Niall Saunders]

Well, last November I set out to build myself a new PC, specifically so that i could justify paying for the full commercial license for PixInsight.

Literally, as my machine was going into final test, Intel announced the i7 - and I had to decide whether to make a last minute change.

My eventual decision was not to bother - and I have not had any regrets.

The spec I ended up with was :-

Processor : Intel® Core™2 Quad Q9550 (4 X 2.83GHz) 1333MHz FSB/12MB Cache
Memory : 4GB CORSAIR XMS2 800MHz - LIFETIME WARRANTY! (2x2GB)
Motherboard : ASUS® P5Q DELUXE: DUAL DDR2, S-ATA II,2 x VGA, 2 x PCI, 2 PCI-E x1
Operating System : Vista™ Home Premium 64-bit Edition + SP1
Hard Drives : 2 x  320GB SERIAL ATA II HARD DRIVE WITH 8MB CACHE (7,200rpm)
CD/DVD Drive : 20x Dual Layer LightScribe DVD Writer ±R/±RW/RAM
CD/DVD Drive : 16x DVD-ROM & 52x CD-ROM Drive
Graphics Card : 512MB GEFORCE 9600GT PCI Express + DVI + TV-OUT
2nd Graphics Card : NONE
Network Facilities : 2 x ONBOARD 10/100/1000 GIGABIT LAN PORT
Power Supply & Case Cooling : 450W Quiet Dual Rail PSU + 120mm Case Fan
Processor Cooling : STANDARD CPU COOLER
Monitor : HANNS.G 28 Inch Wide TFT Silver/Black 1920 x1200 3MS D-Sub, HDMI
External Hard Drive : 2 x 1TB SERIAL ATA II HARD DRIVE WITH 8MB CACHE (7,200rpm), RAID 1, NAS

Price : £1375.00

I could have gone up one level on the Core 2 Quad processor (up to 3.2GHz) - I don't regret not having done so and, in any case, I can always upgrade that component alone, sometime in the future - IF I felt it was necessary (which, at the moment, I don't).

Same goes for the choice of 4Gb memory - in fact I was advised NOT to consider 8GB - because sometimes the system is LESS stable when using 8Gb, Don't ask me why. But, in any case, I have NEVER, EVER, seen my 'memory useage' meter in the Vista Sidebar go up above 75 - 80%. And I am running a networked security camera system on my second Ethernet adaptor 24/7.

I didn't 'want' to choose Vista, but I didn't 'want' to stay with XP. That said, I knew that I was going to 'need' a 64-bit OS, so Vista 64 had to be my choice. And, after all the reservations, it does actually work. Don't wait for Windoze 7 (or 8, or anything else for that matter) - if you are a Windows user (like 99.97636% of other PC users on the planet) and cannot contemplate the change to Mac OS or Linux, then just stick with Vista 64. You won't be disappointed. And, if you cannot face the upgrade to Vista 64, then stick with XP 64.

My only 'regret' is that Vista 64 'Home' does not have the Remote Desktop facilities of Vista 64 'Pro' - but there are (better) ways around the problem.

Don't be tempted to load ALL your hard drive storage into the main case - if you have a problem there, then you couls lose everything (think fire, theft, etc.). Hence I chose anothe NAS to add to my network - this time with built-in RAID. And I keep that unit 'off-site' (and therefore protected from the 'fire and theft' risks).

And I have absolutely NO REGRETS about the ASUS motherboard - they are simply fantastic.

As is the graphics card - plenty fast enough to handle anything I have cared to throw at it. I don't believe that PixInsight has anything in its arsenal that would require a more powerful card.

The monitor was, by far, my best choice. A delight to work with, And, if you REALLY need more screen 'real estate' (more than 1920 x 1200 pixels), then GET TWO of them - but be prepared to have to go to a good eye surgeon and ask them to relocate your eyes closer to your ears !!!

Hope this info is of use to someone.

Cheers,

[Nocturnal]

Sounds like quite a race horse you got there Niall! Thanks for providing so many details.