In Doom 3, seta image_cacheMegs "256" sets the image_cacheMegs limit to 256 megabytes. The cvar documentation describes it as the maximum amount of space set aside for temporarily loading full-sized precompressed images—not a general allocation of system RAM or video memory. Whether 256 is right for your setup is not established by the available examples.
What the setting controls
The Doom 3 cvar reference defines image_cacheMegs as the “maximum MB set aside for temporary loading of full-sized precompressed images.” In the line seta image_cacheMegs "256", seta assigns the variable and saves it to the configuration, while 256 is its configured maximum in megabytes. Doom 3 cvar reference
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Doom 3 BFG Edition | $19.95 | Buy on Amazon |
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This description concerns a temporary image-loading cache. It does not say the game reserves 256 MB of video memory, nor does it define the setting as a general system-RAM allocation.
How it relates to image_useCache
image_cacheMegs and image_useCache are separate cvars. The reference describes image_useCache as “1 = do background load image caching,” while image_cacheMegs specifies the cache-size ceiling. Do not assume that setting one automatically enables the other; check both values in the configuration if you want to know how they are set. Doom 3 cvar reference
#1 Best Overall
- Optimized for Consoles: Doom 3 BFG Edition features 5.1 surround sound, Xbox 360 Achievements, PS3 trophies, improved rendering and lighting, and a new check point save system allowing for smoother progression through the game.
- Stunning 3D Visuals: Doom 3, Resurrection of Evil and the all-new 'Lost Mission' have all been optimized in stereoscopic 3D for Xbox 360 and PlayStation 3, further immersing the player in the demonic world of this terrifying horror masterpiece.
- The Lost Mission: Doom 3 BFG Edition includes an all-new chapter in the Doom 3 experience - 'The Lost Mission', featuring seven heart-pounding single-player levels and a completely new storyline that will have players once again on the edge of their seats.
- The Ultimate Collection: As a special bonus, Doom BFG Edition will also include the original Doom and Doom II games, making it the definitive collection of the revolutionary games developed by the studio that pioneered the first-person shooter genre.
Should you use 256?
Not as a universal recommendation. One example configuration includes both image_useCache "1" and image_cacheMegs "256", while a separate resolution-fix repository uses a cache size of 20. These are examples of differing configurations, not evidence that either value is best for every machine or Doom 3 build. Example configuration
Historical forum advice ties cache settings to the amount of RAM, but the cvar reference does not endorse a RAM-ratio rule. Treat such advice as anecdotal rather than authoritative. Tweakers forum discussion
Rank #2
Editing the line
- Locate the Doom 3 configuration file used by your installation and make a backup before changing it.
- Find the
image_cacheMegsline. If you intend to set the limit to 256 MB, useseta image_cacheMegs "256", preserving the quoted-value syntax shown in the configuration. - Check
image_useCacheseparately if you want background image caching enabled; the documented enabled value is1. - Save the file and launch the game. If you are troubleshooting, change one value at a time so you can identify which change, if any, affects behavior.
Community configuration examples vary, and the setting’s behavior may differ across the original game and engine forks. If the distinction matters for your installation, verify the cvars supported by that specific build. DOOM 3 community configuration discussion
Quick Recap
Best Value
- Intensely realistic and stunning visuals - advanced graphics immerse you in the feel of all-out combat against deadly killing machines
- The action doesn't stop or slow down for a second - collect ammo and health as you plow through all-new levels, each one filled with terror
- Battle new monsters with all-new weapons
- Frightening visual design and murderous intent - ever-changing levels of fear and uncertainty will test your limits
- Vicious multiplayer action within a totally dynamic game world
Rank #4
- Optimized for Consoles: Doom 3 BFG Edition features 5.1 surround sound, Xbox 360 Achievements, PS3 trophies, improved rendering and lighting, and a new check point save system allowing for smoother progression through the game.
- Stunning 3D Visuals: Doom 3, Resurrection of Evil and the all-new 'Lost Mission' have all been optimized in stereoscopic 3D for Xbox 360 and PlayStation 3, further immersing the player in the demonic world of this terrifying horror masterpiece.
- The Lost Mission: Doom 3 BFG Edition includes an all-new chapter in the Doom 3 experience - 'The Lost Mission', featuring seven heart-pounding single-player levels and a completely new storyline that will have players once again on the edge of their seats.
- The Ultimate Collection: As a special bonus, Doom BFG Edition will also include the original Doom and Doom II games, making it the definitive collection of the revolutionary games developed by the studio that pioneered the first-person shooter genre.
- System Requirements: Minimum- OS: Windows vista / Windows 7, Processor: 2.0 GHz dual core, Memory: 3 GB RAM, Graphics: NVIDIA GeForce 9800 GT / ATI Radeon HD 5750, 512 MB video RAM, Hard Drive: 11 GB, Sound: Windows compatible sound card, Recommended- OS: Windows Vista-64 / Windows 7-64, Processor:2.4 GHz dual core, Memory: 3 GB system RAM, Graphics: NVIDIA GeForce GTX 260 / ATI Radeon HD 5850, 768 MB video RAM, Hard Drive: 11 GB, Sound: Windows compatible sound card, Additional: 3D Monitor + compatible glasses
Rank #3
- Intensely realistic and stunning visuals - advanced graphics immerse you in the feel of all-out combat against deadly killing machines
- The action doesn't stop or slow down for a second - collect ammo and health as you plow through all-new levels, each one filled with terror
- Battle new monsters with all-new weapons
- Frightening visual design and murderous intent - ever-changing levels of fear and uncertainty will test your limits
- Vicious multiplayer action within a totally dynamic game world
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