Thermaltake LCGS Reactor u2890 Gaming Desktop (Intel® Core™ Ultra 9 285K, ToughRam 32GB DDR5 6400MT/s RGB Memory, NVIDIA® GeForce RTX™ 5090, 2TB NVMe M.2, WiFi, Windows 11) T6BK-Z890-590-LCS

Thermaltake LCGS Reactor u2890 Gaming Desktop T6BK-Z890-590-LCS

Name: Thermaltake LCGS Reactor u2890 Gaming Desktop (Intel® Core™ Ultra 9 285K, ToughRam 32GB DDR5 6400MT/s RGB Memory, NVIDIA® GeForce RTX™ 5090, 2TB NVMe
Brand: Unbranded
SKU: B0FB15XXWX

Status: Thermaltake LCGS Reactor u2890 Gaming Desktop (Core Ultra 9 285K RTX 5090 gaming PC): Unavailable on Amazon as of 2026-10-21 16:15 UTC. SpecPicks has no in-stock Core Ultra 9 285K RTX 5090 gaming PC on file; an Amazon search for "Core Ultra 9 285K RTX 5090 gaming PC" lists current offers with the same specs. eBay sellers may still list this model new or used.

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Bottom line: The Thermaltake LCGS Reactor u2890 Gaming Desktop T6BK-Z890-590-LCS is a specs-and-price decision rather than a crowd-consensus one in the prebuilt gaming pcs category. Check the specification table below against one or two close alternatives — on price and spec fit, not on star ratings.

Unavailable on Amazon as of 2026-10-21 16:15 UTC

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By Mike Perry, Founder & Editor-in-Chief · Listing data updated 2026-10-21

Mike Perry — Hardware researcher since 2014, focused on GPU performance across gaming, rendering, and local-LLM inference. Synthesises community benchmarks, manufacturer specs, and public forum data into actionable buying guides. About the author →

Pros & Cons

Pros

✓ NVIDIA GeForce RTX 5090, Display Port/HDMI

Cons

✗ Check the listed dimensions, connectors and platform compatibility against your setup before ordering
✗ Price, stock, shipping and returns are set by the retailer and may have changed since this page was last updated

Manufacturer description

What better way to power your battle station than the Reactor u2890. Its unique octagonal prism shape isn't just a statement piece; it's a testament to innovation, designed to offer superior cooling and performance. Powered by the formidable Intel® Core™ Ultra 9 285K processor and the revolutionary RTX 5090 graphics card, this gaming behemoth delivers unmatched performance for an immersive gaming experience. With 32GB of high-speed 6400MT/s Memory and a massive 2TB NVMe SSD, say goodbye to load times and hello to instant action.

SpecPicks Verdict

SpecPicks scored Thermaltake LCGS Reactor u2890 Gaming Desktop T6BK-Z890-590-LCS using a rating × review-volume × price-fit model applied to our editorial and benchmark analysis across the prebuilt gaming pcs category. Compare with similarly-priced alternatives in the prebuilt gaming pcs category before committing. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.

Common buyer scenarios for prebuilt gaming pcs of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.

Key Features

Intel Core Ultra 9 285K CPU, Intel Z890 Chipset motherboard, 32GB DDR5 6400MT/s RGB, 2TB NVMe M.2, WiFi, Windows 11
NVIDIA GeForce RTX 5090, Display Port/HDMI
Enjoy Panoramic Views with 3mm TG Front panels and Excellent Airflow with Perforated Side Panels
Closed Loop Liquid Cooling with 360mm Radiator
Chassis I/O - 1x Type C, 2x USB 3.0, 1x Headphone, 1x Mic Ports

Full Specifications

Brand	Thermaltake
Color	Black
RAM Type	DDR5 RAM
CPU Model	Intel Core i9
CPU Speed	3.7 GHz
Cache Size	32 MB
Model Name	Reactor u2890
Model Year	2021
Resolution	3840 x 2160
Style Name	285KF \| 5090
Aspect Ratio	16:9
Connectivity	USB, WiFi
Display Type	LED
Memory Speed	6400 mt_s
Model Number	T6BK-Z890-590-LCS
Speaker Type	External Speakers Required
Video Output	DisplayPort, HDMI
Built-In Media	RGB Lighting
Cooling Method	Liquid
Keyboard Layout	QWERTY
Full listing title	Thermaltake LCGS Reactor u2890 Gaming Desktop (Intel® Core™ Ultra 9 285K, ToughRam 32GB DDR5 6400MT/s RGB Memory, NVIDIA® GeForce RTX™ 5090, 2TB NVMe M.2, WiFi, Windows 11) T6BK-Z890-590-LCS

Performance Data

View gaming FPS, AI inference throughput, and synthetic scores for the NVIDIA GeForce RTX 5090 — the core hardware component in this product. Benchmarks sourced from TechPowerUp, PassMark, and the r/LocalLLaMA community.

Related benchmarks: Intel Core Ultra 9 285K benchmarks

Which local LLMs fit in 32 GB?

32 GB holds a 30–35B model at Q4 with a long context window; a 70B model runs only with layers resident in system RAM.

✅ 7–9B models (Llama 3.1 8B, Qwen 3 8B) — fits at Q4
✅ 12–14B models (Qwen 3 14B, Phi-4) — fits at Q4
✅ 20–27B models (Gemma 3 27B, Mistral Small) — fits at Q4
✅ 30–35B models (Qwen 3 32B, QwQ 32B) — fits at Q4
❌ 70B models (Llama 3.3 70B, Qwen 2.5 72B) — needs 48 GB+

Across 6 community runs from 4 sources, the NVIDIA GeForce RTX 5090 generates a median 185.9 tok/s on 7–9B models at Q4 (per Hardware Corner).

Per-model VRAM guide: which GPU for which LLM →

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