Hello.

It is my understanding that you need 32 GB RAM to “learn” Houdini (from my experience, 16 GB RAM cuts it waaay too close when compositing heightfield textures), and at least 64 GB to simulate oceans and other small scale stuff (for production).

But what about the RAM speed? Is faster RAM preferred (e.g. 3000 MHz, 3200 MHz) or lower latency ones (e.g. CL13, CL12)?

Eh, it's more about the amount than the speed. You can control the speed of the simulation by controlling the resolution.

At a guess less latency is preferred for non-opencl non-flat memory work and faster speeds for opencl work. Really need to test that hypnosis in consideration of other computer subsystems, i.e. CPU, bios etc

The majority of the latency is due to the memory controller on the cpu. Traditionally Intel CPUs have better latency than AMD. More DIMM modules will generally add more latency than an equivalent amount of memory using fewer sticks (eg, 8*8 vs 4*16), though you'll want to take advantage of dual and quad channel memory wherever possible for increased bandwidth.

Hi,

Enivob
Eh, it's more about the amount than the speed. You can control the speed of the simulation by controlling the resolution.

Yes, the way you use Houdini is the key, I think it's worth to share my two cents I wrote in a tutorial for 3D World mag (Discover Houdini’s terrain toolset, issue 243):

Some default settings in Houdini can annoyingly slow down the interaction with the software, especially with high-resolution terrains. One is that when you select a node in the Network Editor, the viewport tries to display it and its handles, even if the display flag is on another node. To avoid this, switch off the current geometry in the Guides tab in the Display Options dialog.

The other important setting for eliminating lag is in the Geometry Select Mode's pop-up menu (the second on the left viewer control bar). You can switch between Show Display Operator and Show Current Operator. The latter is the default, whereas the former shows just the display flagged node regardless of the selection. The best solution is to bind shortcuts for these two menu items.

I'm afraid that many users don't know/use these and sometimes they pay long seconds for a click. It can be hours on a week, days in a year…