Another workstation build question

[aneverman]

Hi all,

I've read through a lot of the workstation build posts, but seeing as technology changes so quickly I just wanted to check the info was still applicable.

I've been assigned the task of building a dedicated workstation for my university to run PS projects and R statistics calculations.

At this stage we will be using PS to build high accuracy georeferenced DEMs from ~3200 24 MP photos. We are really hoping to process these in one chunk, as we aren't sure what errors will be introduced if we split the photos into chunks, such as random edge effects, and errors with merging the clouds. I don't think we will be building a mesh from the point cloud in PS, we will probably be processing the point cloud in CloudCompare, or ArcGIS. But I guess we can split the point cloud to build meshes and textures if we wanted to for display purposes?

Our budget is around 3000 USD. It really needs to be a workstation rather than a server for IT management reasons.

So my questions are:

1) Is it worth running two intel CPUs if I want to use GPGPU processing for the point cloud building, or am I better to spend the money on two GPUs to speed up the depth map building/point cloud generation? Am I better to go with 4 core 4 Ghz CPUs over 6 core 3.3 Ghz?

2) Can PS utilize two GPUs?

3) Does GPU memory size make much difference? aka am I better to go with lower memory CAD cards for the same price as gaming grade card? I had read that PS can't really make use of the CAD cards due to only using single precision calculations, but that doesn't mean anything to me!

I was looking at the radeon cards, as I read they are better for OpenCL processing, and was looking at the R9 390 or the HD7970, for around the same price. How do you choose between them?

4)Does RAM speed make a lot of difference? Following the spec sheet, we need around 128 GB of RAM to process the number of photos we are looking at, possibly even more. Given our limited budget, we are really looking at DDR3 ram. But would DDR4 be a significant advantage? Would DDR3 2133 be a worthwhile advantage over DDR3 1600?

5) Does a RAID 0 HDD cluster speed things up, or are all the speed gains in the processing? Would I be better off just using a high RPM HDD?


Thanks in advance for any answers!

[dtmcnamara]

1) Is it worth running two intel CPUs if I want to use GPGPU processing for the point cloud building, or am I better to spend the money on two GPUs to speed up the depth map building/point cloud generation? Am I better to go with 4 core 4 Ghz CPUs over 6 core 3.3 Ghz?
     I dont think the extra money is worth it going to 2 CPUs. I would rather save the money and purchase a better single CPU mobo, more ram and a faster single CPU

2) Can PS utilize two GPUs?
    Yes, it will utilize as many GPUs as you can throw at it

3) Does GPU memory size make much difference? aka am I better to go with lower memory CAD cards for the same price as gaming grade card? I had read that PS can't really make use of the CAD cards due to only using single precision calculations, but that doesn't mean anything to me!
     I dont believe so, I may be wrong. I used a Tesla card for some time and was able to monitor the memory useage and it never seemed to go over 1MB of use.

I was looking at the radeon cards, as I read they are better for OpenCL processing, and was looking at the R9 390 or the HD7970, for around the same price. How do you choose between them?
     The R9 390 would run cooler, and pull less power. This would give you the ability to run multiple cards.

4)Does RAM speed make a lot of difference? Following the spec sheet, we need around 128 GB of RAM to process the number of photos we are looking at, possibly even more. Given our limited budget, we are really looking at DDR3 ram. But would DDR4 be a significant advantage? Would DDR3 2133 be a worthwhile advantage over DDR3 1600?
     I have not seen any difference from upgrading from DDR4 2133 to DDR4 3000

5) Does a RAID 0 HDD cluster speed things up, or are all the speed gains in the processing? Would I be better off just using a high RPM HDD?
     Just go with a 1TB SSD as a working drive. They are dirt cheap now and will make sure the data is geting to and from the CPU/RAM as fast as possible

[aneverman]

Thanks dtmcnamara, those are some great insights.