I do run Starsector on a quite low-end computer, but I've noticed Gneiss is by far the hardest system for me to load. On entering a jump point the game pauses for 3-5sec and it's common for me to CTD as I enter, I assume from being out of memory. I'm not sure what specifically about Gneiss causes this as it doesn't seem to have much more to it when compared to other systems except perhaps the way Blackrock and its nearby objects are all chained to one market.
Do you also use Scy or Shadowyard, and in that case do you have the same problem in their systems? It could come from the high rez ring textures we use.
I don't at the moment, but I'll shuffle things around to check in a few minutes.
EDIT: I experience a drop in frame rate when passing through the fluffy ring in Acharon, but otherwise it and Tartarus behave normally (curse SCY's systems spawning on the edges of space!). I jumped into Gneiss again to check that having different mods loaded (I disabled Tiandong and Imperium to enable SCY) wouldn't change the result, and it crashed on me.
Given the log's spam about JPEG, I'm guessing it does have to do with a texture, but I'm the opposite of an expert. It appears to be the same log that came about the previous times it crashed, I just never saved it until now as I'm sadly used to running out of memory.
Spoiler
143252 [Thread-5] ERROR com.fs.starfarer.combat.CombatMain - java.lang.RuntimeException: javax.imageio.IIOException: Insufficient memory (case 4)
java.lang.RuntimeException: javax.imageio.IIOException: Insufficient memory (case 4)
at com.fs.starfarer.util.ReplaceableSprite.update(Unknown Source)
at com.fs.starfarer.campaign.BackgroundAndStars.renderBG(Unknown Source)
at com.fs.starfarer.campaign.BaseLocation.renderBG(Unknown Source)
at com.fs.starfarer.campaign.CampaignEngine.renderBG(Unknown Source)
at com.fs.starfarer.campaign.CampaignState.render(Unknown Source)
at com.fs.starfarer.BaseGameState.traverse(Unknown Source)
at com.fs.state.AppDriver.begin(Unknown Source)
at com.fs.starfarer.combat.CombatMain.main(Unknown Source)
at com.fs.starfarer.StarfarerLauncher$2.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: javax.imageio.IIOException: Insufficient memory (case 4)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.readImage(Native Method)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.readInternal(Unknown Source)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.read(Unknown Source)
at javax.imageio.ImageIO.read(Unknown Source)
at javax.imageio.ImageIO.read(Unknown Source)
at com.fs.graphics.TextureLoader.Ò00000(Unknown Source)
at com.fs.graphics.TextureLoader.o00000(Unknown Source)
at com.fs.graphics.TextureLoader.o00000(Unknown Source)
... 10 more
EDIT2: Now I'm kinda embarrassed; turns out I thought "Fear machine" from Exigency (which I have due to MusicLib) was a Blackrock song. But, I do still enjoy hanging out on the market screen of a Blackrock post to listen to that music, too.