Unit Detail performance impact

[slgrim]

Hi,

I've noticed a very high performance impact during large land battles when Unit Detail is set to High or Ultra and I was hoping someone could shed some light as to what in my rig may be causing this apparent bottleneck.

To illustrate the issue I set all GFX settings to Low/Off except Unit Detail which was left on Ultra. During a replay of a large siege battle my FPS would drop to 25-35 once the armies collide on the walls. In contrast when I set all the settings to Max/On (even VSync) but set Unit Detail to Low the absolute minimum frames I could get was 33 FPS.
Why is it that just this one setting can cripple my rig?

Additionally I also ran GPU-Z and Perfmon in the background and found that, even though my FPS was dropping below 30 during the first test, the maximum load on my GPU was 43% with a mere 540 MB VRAM used (of 1280).
The interesting thing though was my CPU usage. It appeared that one core was sitting between 95-100% usage whilst the rest were below 20% (some were even in a parked state).
Clearly the game isn't taxing my PC so why am I getting below 30 FPS?

Is there anything I can do to run High Unit detail without it crippling my experience?

I'm running:
Core i7 K 875 (OC to ~3300GHz)
GeForce GTX 570 (1280MB)
8 GB DDR3 RAM (PC3-16000)

I've already updated all drivers so no need to suggest that

TL;DR: High/Ultra Unit Detail cripples my FPS even though CPU & GPU load is low.

[Dingo]

S2 can effectively only use a single core of your CPU, that's why you see one core at near 100% load and the others idling (doing OS stuff).

Besides a CPU with faster single core performance, there is not much you can do. But to give you a perspective, I have a 2500k@4.5Ghz (and a 7970@1100Mhz) and if I zoom in very close in a big clash with many units, I get <20fps, LOL. The one thing, besides unit detail, which helps a bit, is to reduce shadow detail to medium. Somehow shadow calculation also taxes the CPU a lot it seems.

[slgrim]

I have a 2500k@4.5Ghz (and a 7970@1100Mhz) and if I zoom in very close in a big clash with many units, I get <20fps, LOL.

Wow that is ridiculous.
Out of curiosity, are there any games which do effectively make use of multiple CPU cores. I've always assumed that all the latest games would.
Thanks for the reply though.

[Iscaran]

Civ 5 uses up to 4 threads (effectively). And its one of the most multi-core games out afaik.

[CYBEREVILRYU]

CA promised that this game would take advantage of multiple cpus, as you can see they broke their promise.It's pointless to get a 4, 6 , or an 8 core processor to play this game.I get better frame rates playing the Witcher 2 and Batman Arkham City than this game on a laptop with these specs Intel(R) Core(TM) i7 CPU M 620 @ 2.67GHz (4 CPUs), ~2.7GHz, 6144MB RAM, ATI Mobility Radeon HD 5850.

[slgrim]

Civ 5 uses up to 4 threads (effectively). And its one of the most multi-core games out afaik.

Good old Sid.

It's rather ironic to see "Enhanced for Intel CORE inside" in the starting videos of S2 when it clearly isn't
What do you think the chances are they'll fix this in FotS?

[Kilgin]

I guess I have to use medium unit detail settings too if this doesn't change with another patch,

does anyone know if another patch is going to be released?

[Iscaran]

Good old Sid.

Apart from the name the game is not Sid...only PARTS of his crew made this game. The master himself did nothing - kinda likely explains why I prefer Civ4 over 5 at any single gaming point .

Well multithreading computing is not as easy as to just put a switch in the code which reads "use more threads"...if it were ANY software would be multithreading from the start.

In fact you have to redesign every code line, every logic algorithm and check for every single one whether or not it depends on others (needs to be calculated in "line") or can be calculated "parallel" to others ("multi-threaded").

Even if you do - there is a limit to which processing can be parallelized.