r9 290 Downclocking Confusion

[Daishiknyte]

First major upgrade in years and I'm already having headaches with it. The r9 290 I put in is having a field day running me in circles trying to figure out what the heck is going on.

In all cases, temperature is maintained at 93C or below by messing with maximum fan rates. 55% seems to be the magic number for me. Resolution is 1920x1200. Charts were made by me running around on a level and playing through a section of the game for roughly 8-10 minutes. Apologies in advance for the big pictures. It's a bit late and I didn't see an easier way


Case 1) Using Uniqen Heaven and Valley benchmarks the card is placed under a constant 100% load. At load, the 290 is temperature stable at 93C and running at its rated speed of 947Mhz.
http://i.imgur.com/6tb2HF1.png
http://i.imgur.com/CJ04YEi.png


Case 2) Playing ARMA 3 in both full screen windowed and fullscreen graphics modes. Temperature is stable or below 93C at all times. The card is constantly bouncing between some percentage of use (typically 75-100) and 0. This is constant and rapid. The card will not reach rated speed at any point during play. The speed is often fluctuating between 650Mhz and 850Mhz at any given point and does not stabilize. While this is happening, framerates hover in the low 20s to the mid 30s. Single player and multiplayer.
http://i.imgur.com/rChPHwt.png


Case 3) Playing Kerbal Space Center. Temperature is again stable and well below threshhold. GPU usage maxes out at a fairly constant 100% with a couple bumps and drops here and there. Core clock rating will not go above 680Mhz or so. FPS limit was raised to 180 during this test and was not in danger of being reached.

Case 4) Skyrim + Graphics mods. 1st off, wow, got to love that extra graphics ram. Temperature is, you guessed it, still low. GPU usage is all over the board. 100% to 0% and back. Clock rate comes in a bit lower in the 850 range. However, this one I can account for because of the 60 FPS limit being reached and held, unlike some of the others.

Case 5) Dishonored. Similar to Skyrim. Game hits framerate cap without a problem. Odd though the GPU usage spikes to 100% and falls to 0 for significant periods.
http://i.imgur.com/Yxp1J5K.png

Case 6) Borderlands 2. GPU usage and clock speeds actually seem reasonable this time around. GPU usage showed what I'd consider 'normal' amounts of variation as I ran around the maps. Best of all, GPU speed pegged at 947Mhz and stayed there except for a pair of cutscenes. Wish I knew what the difference between BL2 and everything else is.
http://i.imgur.com/a9hwzPr.png

Case 7) Mirror's Edge. Not sure why I'm even mentioning this. It's obvious from the getgo the game is limited at 60fps and the 290 doesn't have to even try. Hell, it spends most of its time sitting barely above idle. My old GTX460 always chugged a bit.
http://i.imgur.com/9wD4DAo.png

Case 😎 Civilization 5. Now THIS is how I'd expect a game to run. Without a FPS cap, Civ5 happily eats every resource you throw at it. GPU usage is maxed out and STABLE. Core clock is maxed at 947Mhz and STABLE. Why aren't the other games running like this?
http://i.imgur.com/syPJ2S3.png

Case 9) Crysis 1. I remember when Crysis first came out...to see the game engine humbled by a single graphics card is still an amazing thing. And damn, it's still one of the best looking games out there. GPU usage seemed to hop around only when around AI. When enjoying the scenery, usage stayed steady at 100%. Either way, the core clock remained pegged at max. Overall, it felt stable.
http://i.imgur.com/OF5JKOJ.png

So at the end of the day, I'm left confused. On one hand, the card performs beyond anything I expected, completely dominating each of the games and letting me crank up settings to levels I didn't think existed. However, I'm baffled and frustrated by the inconsistent performance in a number of games (some not included), particularly ARMA 3. With the understanding this new generation of cards is limited thermally, I cannot figure out why it continues to underclock itself and act so wildly when there's quite a bit of heat room left to play with. Even enforcing higher fan speeds doesn't mellow out the seizure inducing usage and clock bouncing. At least with Borderlands 2, the performance maintained a high enough level to prevent game stuttering or low FPS. ARMA 3 doesn't even have that excuse, barely cresting 40 fps during most of the session.

Any ideas why ARMA 3 and others show issues with the seemingly out of place settings?