---
title: "15 RTX 4090 Graphics Cards in a Single PC: Enthusiast Builds a Workstation Drawing Nearly 8 kW"
description: "3D visualization specialist Simone Marulli has built a workstation featuring 15 RTX 4090 graphics cards on a single board: 360 GB VRAM, 245,760 CUDA cores, and nearly 8 kW power consumption. The system set records in OctaneBench and V-Ray 6."
date: 2026-10-28T19:09:10.352Z
lang: en
url: https://xab.info/en/posts/15-rtx-4090-graphics-cards-single-pc
tags: [rtx-4090, workstation, 3d-rendering, nvidia, gpu]
author: "Alexander Buran, Roman V."
publisher: "XAB.info"
---

# 15 RTX 4090 Graphics Cards in a Single PC: Enthusiast Builds a Workstation Drawing Nearly 8 kW

![Motherboard with MSI GeForce RTX 4090 SUPRIM Liquid graphics cards and their retail boxes](https://xab.info/media/2026/10/28/15-videokart-rtx-4090-v-odnom-pk/15-videokart-rtx-4090-v-odnom-pk-1.webp)

## Key Points

- 15 MSI GeForce RTX 4090 SUPRIM Liquid graphics cards operate on a single motherboard
- A total of 360 GB VRAM and 245,760 CUDA cores; powered by five 1,600W PSUs, consumption up to ~8 kW
- Record results: 21,171.8 points in OctaneBench 2020.1.5 (RTX) and 172,615 vpaths in V-Ray 6
- The author does not disclose the method used to mount 15 full-size GPUs on the board

3D visualization specialist Simone Marulli from Marulli Studio has built a workstation featuring fifteen Nvidia GeForce RTX 4090 graphics cards operating simultaneously on a single motherboard. The system is designed for professional rendering of complex 3D scenes and, according to published data, has achieved record results in specialized benchmarks like OctaneBench and V-Ray 6. This project has become one of the most massive private multi-GPU workstation builds reported in specialized media outlets.

###

### From One Card to Fifteen: Project Chronology

Work on the system began in December 2022 and took nearly a year. Marulli progressively increased the number of accelerators: starting from one graphics card, moving to two, then four, and eight, before finally bringing the configuration to fifteen. This step-by-step approach allowed him to fine-tune power delivery, cooling, and firmware as the load grew. Judging by published photographs, the station uses MSI GeForce RTX 4090 SUPRIM Liquid cards — a flagship liquid-cooled model critical for high-density layouts.

###

### The "Mystery" of Housing 15 GPUs on a Single Board

The key technical puzzle of the build is how fifteen full-size accelerators were accommodated. Most modern workstation motherboards feature a maximum of seven full-size PCIe slots, making it impossible to install 15 cards through standard means. Marulli does not disclose architectural solutions or implementation details: exactly how he managed bandwidth, power delivery, and physical layout remains his secret. Nevertheless, the system's total specifications are impressive: each card features 24 GB of VRAM, providing a staggering 360 GB of VRAM for the entire station, while the total CUDA core count reaches 245,760.

### Power Supply and Consumption Rivaling a Small Substation

To power the fifteen flagship accelerators, five 1,600W power supply units are used — totaling 8 kW. During active 3D rendering, the workstation's power consumption reaches nearly 8 kW, comparable to the load of multiple household appliances running simultaneously. This emphasizes that such configurations require not only a well-designed electrical grid but also serious engineering in current distribution and cooling.

### Record-Breaking Benchmark Results

In the OctaneBench 2020.1.5 test with RTX mode enabled, the system scored 21,171.8 points, while the V-Ray 6 Benchmark result hit 172,615 vpaths. According to the author, both figures sit at the top of their respective public leaderboards, confirming the practical efficiency of the multi-GPU configuration for rendering tasks. For professional studios where render times directly impact project deadlines, such a workstation can drastically cut down complex scene calculation times.

### Context: The RTX 4090 Market and Counterfeit Risks

The emergence of such powerful builds unfolds against the backdrop of an active flagship accelerator market, where specialized media outlets have reported fraudulent schemes involving the sale of RTX 4090 dummy cards on Asian marketplaces. This makes public case studies like Marulli's station especially valuable: they demonstrate real working configurations and help separate proven engineering solutions from market noise. For enthusiasts and professionals, the build remains a vivid example of how far GPU architecture can be scaled within a single system.

## Fact-Check & Sources

- [15 видеокарт RTX 4090 в одном компьютере. Энтузиаст создал по-настоящему мощную рабочую станцию, она пожирает почти 8 кВт](https://www.ixbt.com/news/2026/10/28/15-videokart-rtx-4090-v-odnom-kompiutere-entuziast-sozdal-po-nastoiashhemu-moshhnuiu-rabocuiu-stanciiu-ona-poziraet-pocti-8-kvt.html) - Primary source: author, chronology (December 2022), 15×RTX 4090 SUPRIM Liquid, 360 GB VRAM, 245,760 CUDA, 5×1600W, ~8 kW, OctaneBench results 21,171.8 and V-Ray 6 172,615 vpaths.
- [Мошенники начали продавать муляжи видеокарты RTX 4090](https://www.gazeta.ru/tech/news/2026/06/18/28715911.shtml) - Used as market context (fraudulent RTX 4090 schemes on marketplaces); does not contradict the main article's facts or introduce discrepancies.

## FAQ

### How many graphics cards and what model are used in Marulli's workstation?

Fifteen MSI GeForce RTX 4090 SUPRIM Liquid graphics cards operating on a single motherboard.

### What are the total specifications of the system?

The total video memory is 360 GB (24 GB per card) with a total of 245,760 CUDA cores. Power is supplied by five 1,600W power supply units.

### How much power does the station consume and what results did it achieve?

During rendering, consumption reaches nearly 8 kW. In OctaneBench 2020.1.5 (RTX), it scored 21,171.8 points; in V-Ray 6 Benchmark, it hit 172,615 vpaths, with both figures topping the leaderboards.

### How was it possible to install 15 full-size GPUs when boards typically have a maximum of 7 PCIe slots?

The author does not disclose architectural solutions or implementation details; the connection and layout method remains his secret.