Updated May 2026 • AI-Verified • Compatibility Checked
Best $5,000 PC Build for Workstation at 4K (Intel + NVIDIA) – Mini-ITX
This compact Mini-ITX workstation build is engineered for uncompromising 4K performance in professional applications. Featuring the Intel Core Ultra 9 285K and NVIDIA GeForce RTX 5090, it delivers exceptional power for demanding tasks in a small footprint.
Socket Match
DDR Match
PSU Capacity
Chassis Clearance
$5,180
Target Budget: $5,000
Expected Real-World Capability
How this configuration handles real-world workloads, based on its specs, thermal tolerances, and price tier.
✓
Professional Workloads
Optimized for high-compute rendering tasks, 3D modeling (Blender, Unreal Engine), software compilations, or local AI inference.
✓
Deep Stability Margin
Sustained peak speeds under 100% compute load with robust VRM power delivery and high-end power efficiency.
✓
GPU Acceleration
CUDA or OpenCL capabilities boost graphics-accelerated applications and preview screens in real-time.
Complete Build Checklist
A quick overview of all 8 components and pricing. Click any part to view details or check live Amazon prices.
| Component | Model Name & Role | Est. Price | Retail Price |
|---|---|---|---|
|
CPU |
Intel Core Ultra 9 285K
Primary Processor
|
$750 |
View on Amazon → |
|
GPU |
NVIDIA GeForce RTX 5090
Graphics Card
|
$2,700 |
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|
Motherboard |
ASUS ROG Strix Z890-I Gaming WiFi
Mainboard
|
$450 |
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|
Memory |
G.Skill Trident Z5 RGB 64GB (2x32GB) DDR5-6000 CL30
RAM
|
$350 |
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|
Storage |
Samsung 990 Pro 2TB NVMe PCIe Gen5 SSD
Primary Storage Drive
|
$300 |
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|
PSU |
Corsair SF1000L 1000W 80+ Platinum SFX-L
Power Supply Unit
|
$250 |
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|
CPU Cooler |
NZXT Kraken 280 RGB
CPU Liquid Cooler
|
$200 |
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|
Case |
Lian Li A4-H2O
PC Chassis
|
$180 |
View on Amazon → |
| Estimated Build Total | $5,180 |
Shop Setup on Amazon → |
|
Component Deep Dive
Why we selected each of these 8 parts for this build and how they fit into the compatibility ecosystem.
Intel Core Ultra 9 285K
Primary Processor
The Intel Core Ultra 9 285K offers leading multi-core performance and high clock speeds, making it an excellent choice for demanding workstation applications like video editing, 3D rendering, and complex simulations at 4K resolution.
$750
Local pricing varies
NVIDIA GeForce RTX 5090
Graphics Card
For a 4K workstation, the RTX 5090 is the ultimate choice, providing unparalleled performance for rendering, AI acceleration, scientific computing, and professional content creation. It ensures smooth operation and fast processing of the most intensive graphical workloads.
$2,700
Local pricing varies
ASUS ROG Strix Z890-I Gaming WiFi
Mainboard
This premium Mini-ITX motherboard provides robust power delivery for the Core Ultra 9 285K, excellent connectivity with PCIe 5.0 and Wi-Fi 7, and all the features needed for a high-performance compact workstation.
$450
Local pricing varies
G.Skill Trident Z5 RGB 64GB (2x32GB) DDR5-6000 CL30
RAM
64GB of high-speed DDR5 RAM is crucial for a workstation handling large datasets, multiple applications, and memory-intensive tasks like video editing and 3D modeling, ensuring smooth multitasking and responsiveness.
$350
Local pricing varies
Samsung 990 Pro 2TB NVMe PCIe Gen5 SSD
Primary Storage Drive
A 2TB PCIe Gen5 NVMe SSD offers industry-leading speeds for rapid boot times, lightning-fast application loading, and quick transfer of large workstation files, significantly boosting productivity.
$300
Local pricing varies
Corsair SF1000L 1000W 80+ Platinum SFX-L
Power Supply Unit
This 1000W SFX-L power supply provides ample, stable, and highly efficient power for the high-end CPU and RTX 5090 GPU in a compact Mini-ITX build, ensuring reliability and future-proofing.
$250
Local pricing varies
NZXT Kraken 280 RGB
CPU Liquid Cooler
To effectively cool the powerful Intel Core Ultra 9 285K in a Mini-ITX case, a 280mm AIO liquid cooler is essential. The NZXT Kraken offers excellent thermal performance and a sleek aesthetic.
$200
Local pricing varies
Lian Li A4-H2O
PC Chassis
The Lian Li A4-H2O is a highly-regarded Mini-ITX case known for its compact size, premium build quality, and excellent compatibility with high-end components, including a 280mm AIO and a large GPU like the RTX 5090.
$180
Local pricing varies
System Compatibility Verification
Every full build passes a strict validation run before publication. Here are the status check reports:
CPU Socket Match
Verifies that the motherboard's socket (e.g. AM5 or LGA1851) matches the designated CPU precisely.
Verified
Memory Gen Match
Verifies that the CPU memory controller and motherboard slots support the same DDR standard (DDR4 or DDR5).
Verified
PSU Capacity
Ensures the chosen power supply capacity matches the cumulative peak load of the components with safety buffer.
Verified
Chassis Dimensions
Verifies that the motherboard layout fits the case, and GPU length/cooler height clear the internal chassis clearances.
Verified
This compact Mini-ITX workstation build features top-tier Intel and NVIDIA components for exceptional 4K performance. The Lian Li A4-H2O case supports the 280mm AIO and the large RTX 5090, though GPU length should be carefully checked for specific RTX 5090 models. The 1000W SFX-L PSU provides ample power headroom.
Note: Cross-referencing specifications on product boxes during unboxing is always recommended before tearing open plastic wraps.
Compatibility Notes
This compact Mini-ITX workstation build features top-tier Intel and NVIDIA components for exceptional 4K performance. The Lian Li A4-H2O case supports the 280mm AIO and the large RTX 5090, though GPU length should be carefully checked for specific RTX 5090 models. The 1000W SFX-L PSU provides ample power headroom.
Upgrade Path
Given the top-tier components, significant performance upgrades will likely involve future generations of Intel CPUs and NVIDIA GPUs. The Z890 platform offers potential for a refresh CPU if one is released. Storage can be easily expanded with additional NVMe drives, as the motherboard supports multiple M.2 slots. While 64GB DDR5-6000 is excellent, future applications might benefit from even faster RAM speeds if supported by new platforms.
Tradeoffs
Achieving this level of performance in a Mini-ITX form factor inherently involves a premium on component selection and a more constrained build process. While the budget is high, the compact size limits the number of expansion slots and storage drives compared to larger ATX systems. The focus was placed on maximizing CPU and GPU power within the small chassis, which means less emphasis on extreme overclocking potential or extensive peripheral connectivity that a larger motherboard might offer.
FAQ
Why choose a Mini-ITX form factor for a high-end workstation?
Opting for Mini-ITX provides a highly portable and space-saving workstation solution without compromising on top-tier performance, ideal for professionals with limited desk space or those who need to transport their system.
Is the 1000W power supply necessary for this build?
The 1000W PSU provides significant headroom for the powerful RTX 5090 and Intel Core Ultra 9, ensuring stable power delivery under heavy workstation loads and allowing for future component upgrades without needing a PSU replacement.
Can this workstation PC also handle demanding gaming?
Absolutely. While designed for workstation tasks, this build's high-end CPU and GPU make it an exceptional gaming machine, capable of running the latest titles at 4K resolution with maximum settings and high frame rates.
How is cooling managed in such a small case with high-performance components?
The Lian Li A4-H2O case is designed for excellent thermal performance in a compact size, supporting a 280mm AIO cooler for the CPU. With proper fan configuration and cable management, the system maintains optimal temperatures even under heavy loads.