Hardware Specifications

The TetherBox software is compatible with Intel/AMD and ARM-based systems running Linux. This guide helps select appropriate hardware for various deployment sizes.

CPU Requirements

Benchmark: GeekBench 6 Multi-Core

We use GeekBench 6 Multi-Core scores as they reflect real-world multi-threaded performance, which is how TetherBox processes camera streams.

Rule of thumb: ~150 GeekBench 6 points per 4K camera

All scores in this document are GeekBench 6 Multi-Core (verified January 2026). GeekBench 5 scores are not comparable and should not be used.

To estimate camera capacity:

1. Search for your CPU on GeekBench Browser or CPU Monkey
2. Look up the GeekBench 6 Multi-Core score
3. Divide by 150 to get estimated 4K camera count

Baseline estimates: Assume 4K cameras recording at 8Mbit with H.264 High profile, and analytics processed at 720p @ 3fps with H.264 Baseline profile (optimal balance of accuracy and performance).

Capacity scaling by analytics resolution and framerate:

• Low resolution (≤480p @ 3fps): 2-3× baseline capacity - sufficient for most analytics use cases including motion detection, object detection, and facial recognition
• Standard resolution (720p @ 3fps): Baseline capacity (as per estimates) - recommended default
• High resolution (≥1080p @ 3fps): ~50% of baseline (uses 2× more CPU per camera)
• High resolution (≥1080p @ >3fps): Even lower capacity - CPU usage increases further with framerate

Note: There is no practical benefit to using analytics resolution above 1080p unless you require very high-resolution time-lapse images.

Key insight: Recording and analytics are independent streams. You can record at 4K with H.264 High profile while processing analytics at lower resolution with Baseline profile. 720p @ 3fps with Baseline profile is the recommended default - excellent accuracy with optimal performance. Field deployments show systems routinely handling 2-3× the estimated camera count when using ≤480p analytics.

CPU optimization options (reduce load without affecting recording quality):

• Analytics profile: CRITICAL - Use H.264 Baseline or Main profile for analytics (recording remains High profile) - High profile can increase load 30-50% per camera
• Analytics resolution: Lower to ≤480p (recording remains at full 4K resolution)
• Analytics framerate: Keep at 3fps (analytics doesn't need 25fps) - higher framerates dramatically increase CPU load
• Analytics bitrate: Limit to 1-2 Mbps for analytics stream (recording stream remains full quality)

Storage optimization (for systems with high IO wait >20%):

• Recording bitrate: Reduce to lower write throughput (e.g., from 8Mbit to 4-6Mbit)
• Recording profile: Switch from H.264 High profile to Main or Baseline profile
• Recording framerate: Reduce from 25fps to 15fps if high-framerate playback not required
• Recording resolution: Lower recording resolution if storage performance is severely limited

Example capacities for Intel N100 (2,840 GeekBench 6 points):

• 19 cameras at 4K recording @ 8Mbit (High profile) with 720p @ 3fps analytics (Baseline profile) - baseline configuration
• 38-57 cameras at 4K recording @ 8Mbit (High profile) with ≤480p @ 3fps analytics (Baseline profile) - field-validated
• 9-10 cameras at 4K recording @ 8Mbit (High profile) with ≥1080p @ 3fps analytics (Baseline profile)

CPU Reference Table

These are common CPUs used in TetherBox deployments. Some systems have been running reliably for over 10 years - we continue to support and push updates to all systems regardless of age.

Sorted by performance (highest to lowest). All scores are GeekBench 6 Multi-Core verified from official sources.

Key Considerations

Analytics Resolution: High resolution (≥1080p) analytics uses approximately 1.9× more CPU per camera than low resolution (≤480p) analytics. This is the most significant factor affecting camera capacity.

Storage Performance: If a TetherBox shows high CPU load despite being within camera recommendations, check the IO wait percentage on the dashboard. Values exceeding 20% indicate storage bottlenecks rather than CPU limitations. Storage issues can manifest as apparent CPU overload but are resolved by replacing storage hardware, not upgrading the CPU.

Recommendations by Deployment Size

RAM Requirements

Formula: 2GB minimum, add 1GB per 4 cameras for standard analytics

Standard Analytics (≤720p)

Most deployments use standard analytics resolution for optimal performance and capacity.

High Analytics (>720p)

High-resolution analytics requires approximately 1.5× more RAM than standard analytics.

Storage Requirements

Storage depends on resolution, motion activity, and retention period. Below are estimates for 30 days retention per camera:

Recommended Storage Hardware

USB Storage Options (in Order of Preference)

1. USB SSD (recommended) - Plug-and-play, high speed, reliable, excellent endurance
2. USB HDD (24/7 rated) - Suitable for lower camera counts, must be surveillance/NAS-class
3. USB to SATA/NVMe adapter - Flexible, use quality adapters from reputable manufacturers

Hard Drive Selection

Recommended HDD Models

Choose NAS or Surveillance-class drives designed for 24/7 high-write workloads:

• Seagate: IronWolf (NAS) or SkyHawk (Surveillance)
• Western Digital: Red (NAS) or Purple (Surveillance)
• Toshiba: N300 (NAS) or S300 (Surveillance)

Storage Warnings

• Never use USB memory sticks - Not designed for continuous writes, will fail quickly
• Avoid "basic/value" HDDs - Often fail after 1-2 years of 24/7 use
• Use quality USB adapters - Cheap adapters cause misreported failures or system freezes
• Avoid manual power switches - Enclosures requiring manual intervention after power loss are problematic

Diagnosing Storage Performance Issues

If a TetherBox shows high CPU load despite being within camera recommendations, check IO wait percentage on the dashboard:

• >20% IO wait: Storage bottleneck detected - investigate immediately
• Common causes:
  • Failing USB storage devices (end of life, bad sectors)
  • Poor quality USB controllers or adapters
  • Slow or degraded RAID arrays
  • Dying HDDs showing early failure signs
  • USB 2.0 connections (should use USB 3.0+)

Storage bottlenecks can manifest as CPU overload but are resolved by replacing storage hardware, not upgrading the CPU. The TetherBox dashboard displays IO wait percentage under system metrics.

Graphics / GPU

Standard deployments: No dedicated GPU required. TetherBox uses onboard graphics or CPU for processing.

Hardware acceleration: TetherBox automatically utilises Nvidia, AMD, or Intel dedicated graphics when available.

Analytics: Out of the box, TetherBox leverages any analytics built into your Cameras or recorder. For edge analytics requirements (local AI/ML processing), please contact TetherX support to discuss GPU requirements for your specific use case.

Operating System Installation

For complete installation instructions including partitioning and configuration, see Installing Operating System.

Cloud Backup (optional)

For off-site redundancy, enable TetherX Cloud Backup to protect critical footage against theft, damage, or local disasters.

References

• CPU Monkey - Compare CPU performance across generations
• GeekBench Browser - Search specific CPU benchmarks