I'd like to build a workstation for one of my CAD programs called AspenPLUS. That it's purpose-built for AspenPLUS imposes a few important constraints.
I have a bunch of questions which I suspect are pretty tough to answer, but any help on any of them would be greatly appreciated.
Constraints
1. It has to be on Windows 7 due to a whole host of compatibility issues which are notoriously difficult to deal with. I'll be using Windows 7 Enterprise x64.1
2. AspenPLUS will use one and only one core for its runs.2
Questions
1. I assume that my workstation will work at about [the core frequency] times [the core multiplier] in operations per second. Is this accurate?
2. If I get a CPU with a lot of cache, how would it affect program operation? Would the computer automatically use the cache, or would it not know to do so and the extra cache go to waste? Would the 30MB of cache on new, high-end Xeons be very useful?
3. True or false: I want one core per running Aspen simulation plus one core for the OS and other background programs.
4. Since the computer will run nothing but Aspen and the OS, I doubt that it would require more than 28GB of harddrive space. If I get 64GB of RAM, then I can dedicate 32GB to a RAM disk and run the whole thing off of DDR3. Would this be helpful, or would it actually cause a bottleneck with communications to the RAM (since RAM's now doing double duty as memeory and storage) which would slow things down?
5. Not planning on doing much in the way of intensive I/O, and it wouldn't be a problem to backup my data every day. Would RAID still be useful, or can I just give it a pass?
6. Would there be any point in splurging on a high-end graphics card? (Aspen has pretty minimalistic graphics.)
7. How does one choose the optimal type of RAM? (The Xeon E7-8870 supports up to 1333MHz, yet the linked page notes that its max speed is 1066MHz. Does this imply that the 1066 is faster than the 1333 for it, or merely that the 1333 enjoys no advantage?)
8. Anyone happen to know what the odds are that a better Xeon will be coming out soon? And if it'd be much more expensive at introduction or not?
9. Say that I'm at the workstation (as opposed to remoting into it) and I want three screens. What sort of equipment would be necessary for this beyond the screens themselves? Just a second graphics card?
Xeon Comparison
Xeon X5687: 4 cores; 3.6GHz; 27x multiplier; 4x256kB L2 cache; 12MB L3 cache; 2x6.4GT/s bus. (1663USD)
Xeon E7-8870: 10 cores; 2.4GHz; 18x multiplier; 10x256kB L2 cache; 30MB L3 cache; 4x6.4GT/s bus. (4616 USD)
Since 27x3.6GHz is 2.25 times higher than 18x2.4GHz, the much cheaper X5687 would be the ticket for this purpose?
Weird observation: The X5687 supports up to 288GB RAM while the far more expensive and more-cored Xeon E7-8870 only supports 32GB RAM. Windows 7 itself is limited to 192GB RAM.
See: List of Xeon processors for numbers. I suggest using Ctrl+F to find specific Xeon's.
Notes
Like a cluster, I'd probably want to remote into it sometimes, and I may end up offering use of it to my coworkers. This is a minor consideration, but if it brings up any unique issues I'd be interested in knowing.
Footnotes
1I'd be open to the idea of using some recent version of Windows Server if there's any expected gain to be had there, but unless there's motivation to move in that direction, I won't mess with it.
2So far as I know, anyway. On my dual-core laptop, it uses up to 50% CPU time when processing. It occasionally hits 51% for a moment but I suspect that these are estimation errors.