Some people have reported issues with low FPS or even CTDs when they enter the main cavern of Coldhaven.
If your computer tries to load more into memory than it can handle, you will crash to desktop (CTD).
I created Coldhaven as an interior cell so it would fit in better with Vampire mods - some have sun damage or sun penalties if in an exterior cell during daylight hours. Normally, larger cells like Blackreach are set up as exterior cells which mimic an interior ... but I didn't do that here. It's hard to say if things would have been more stable or not.
UPDATE: We have determined that many crashes or FPS issues may be due to people using 2K or even 4K texture packs. As of version 1.4 I have hand edited many meshes and textures so they are more memory friendly when you enter the main cavern of Coldhaven. This should help.
Here are some things to try:
1) Before entering the main chamber, open my MCM and go to the FPS page. You can disable certain objects from loading in the game here. Perhaps too many objects are loading and it is taxing your system?
2) Before entering the main chamber, open your console and type pcb then hit <ENTER>. This purges cell buffers (removes information already loaded from other cells) so you have more memory available. https://skyrimcommands.com/command/purgecellbuffers
3) You can download my Lighting Template Tweak (from my Nexus pages). It edits the lighting template in the main cavern so the fog is closer and object clip at a shorter distance. It is a very small .esp file, and it MUST be loaded after my main mod. https://www.creationkit.com/index.php?title=Lighting_Template
5) You can change the setting 'iTexMipMapSkip=1' in Skyrimprefs.ini. It does work, but it means people will either have to keep changing this value whenever entering Coldhaven, or they could keep this figure but not get the benefit of their 2K texture packs (many thanks to Tattwood for this information). This tells the game to discard the highest resolution mipmap for all textures, and scale everything down. Thus, a 2K texture will be 1K, and 1K textures will decline to 512 pixel.
https://wiki.step-project.com/Guide:SkyrimPrefs_INI/Display#iTexMipMapSkip
6) You can install ENBBoost. It may be a bit difficult to set up, but there are many excellent guides and videos you can Google that will walk you through it. It really helps Skyrim become more stable (especially Oldrim).
Maybe this video might help?
I don't have the best computer by any means, and it is quite old (8 years I think?). Maybe some information about my current computer will help you with comparing/diagnosing.
What are my PC specs?
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System Information
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Time of this report: 3/30/2020, 13:15:42
Machine name: DESKTOP
Machine Id: {A3315294-12ED-4407-A442-24D588127C7F}
Operating System: Windows 10 Home 64-bit (10.0, Build 18362) (18362.19h1_release.190318-1202)
Language: English (Regional Setting: English)
System Manufacturer: System manufacturer
System Model: System Product Name
BIOS: BIOS Date: 02/24/10 14:05:48 Ver: 08.00.15 (type: BIOS)
Processor: Intel(R) Core(TM) i7 CPU930 @ 2.80GHz (8 CPUs), ~2.8GHz
Memory: 24576MB RAM
Available OS Memory: 24568MB RAM
Page File: 11404MB used, 25162MB available
Windows Dir: C:\WINDOWS
DirectX Version: DirectX 12
DX Setup Parameters: Not found
User DPI Setting: 96 DPI (100 percent)
System DPI Setting: 144 DPI (150 percent)
DWM DPI Scaling: UnKnown
Miracast: Available, with HDCP
Microsoft Graphics Hybrid: Not Supported
DirectX Database Version: Unknown
DxDiag Version: 10.00.18362.0387 64bit Unicode
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Display Devices
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Card name: NVIDIA GeForce GTX 1050 Ti
Manufacturer: NVIDIA
Chip type: GeForce GTX 1050 Ti
DAC type: Integrated RAMDAC
Device Type: Full Device (POST)
Device Key: Enum\PCI\VEN_10DE&DEV_1C82&SUBSYS_86131043&REV_A1
Device Status: 0180200A [DN_DRIVER_LOADED|DN_STARTED|DN_DISABLEABLE|DN_NT_ENUMERATOR|DN_NT_DRIVER]
Device Problem Code: No Problem
Driver Problem Code: Unknown
Display Memory: 16301 MB
Dedicated Memory: 4018 MB
Shared Memory: 12283 MB
Current Mode: 2560 x 1440 (32 bit) (60Hz)
HDR Support: Supported
Display Topology: Internal
Display Color Space: DXGI_COLOR_SPACE_RGB_FULL_G22_NONE_P709
Color Primaries: Red(0.644531,0.334961), Green(0.304688,0.629883), Blue(0.148438,0.049805), White Point(0.313477,0.329102)
Display Luminance: Min Luminance = 0.010000, Max Luminance = 1499.000000, MaxFullFrameLuminance = 799.000000
Monitor Name: Generic PnP Monitor
Monitor Model: 32ML600
Monitor Id: GSM772D
Native Mode: 1920 x 1080(p) (60.000Hz)
Output Type: HDMI