OWC
OWC Mercury Helios 3S Thunderbolt 3 Single Slot PCIe Card Expansion Solution
Best PCIe expansion for creative professionals using compact workstations.
Expand your creative workstation with the OWC Mercury Helios 3S, a versatile PCIe card expansion solution for Thunderbolt 3 equipped computers. This chassis enables desktop-class performance for specialized cards like high-speed RAID controllers or professional audio interfaces, ideal for mobile or compact setups. It offers dual Thunderbolt 3 ports for 40 Gb/s speeds and daisy-chaining, plus 85W power delivery to charge your laptop. With DisplayPort 1.4 support for up to 8K displays, it seamlessly integrates into both Mac and Windows workflows.
$249.99
Owner Satisfaction
4.6
/ 5
Category Rank
19
/ 824
#19 in Laptop Docking Stations
Price vs Category Average
+20%
Above average
Expansion Slots
13.0164
/ x PCIe x (x mode)
Who it's for
- Creative professionals needing high-speed data transfer and capture
- Laptop users wanting a streamlined, single-cable workstation setup
- Audio and video editors requiring versatile hardware expansion
Who should skip it
- Power users requiring multiple specialized PCIe cards simultaneously
- Budget-conscious buyers comparing costs against internal desktop upgrades
- Gamers or engineers needing high-end, power-hungry graphics cards
Performance breakdown
Data Throughput
Thunderbolt 3 speeds ensure zero bottlenecks for high-bandwidth PCIe cards.
Power Delivery
85W output keeps most professional laptops charged during intensive creative workflows.
Build Quality
Rugged aluminum chassis provides excellent durability for mobile studio setups.
Display Versatility
DisplayPort 1.4 support handles high-resolution 8K monitors with ease.
Ease of Setup
True plug-and-play functionality eliminates the need for complex driver installations.
Expansion Flexibility
Single-slot design is perfect for specialized tasks but limits multi-card configurations.
Key Specs
Expansion Slots
1x PCIe 3.0 x16 (x4 mode)
System Connection
Thunderbolt 3
Inputs/Outputs
1x USB-C (Thunderbolt 3), 1x DisplayPort 1.4
Power Delivery
85W to host
Dimensions
Width: 9.2 in, Height: 5.6 in, Length: 3.2 in
Weight
3.64 lb
Construction Material
Aluminum
OS Compatibility
macOS 10.13 or later and Windows 10/11
Features
- Connects PCIe cards to Thunderbolt 3 systems at 40 Gb/s.
- Supports full-height, half-length PCIe cards.
- Dual Thunderbolt 3 ports for daisy-chaining.
- Provides 85W power delivery to charge your laptop.
- Includes DisplayPort 1.4 for up to 8K display support.
- Plug-and-play functionality, no extra drivers needed.
- Backward compatible with older Thunderbolt devices.
- Ideal for video, audio, and storage integration.
What customers say
The OWC Mercury Helios 3S garners strong praise for its robust quality and exceptional performance, making it vital for creative professionals needing more connectivity. Users appreciate the durable aluminum build, reflecting OWC's reputation for premium hardware. The core benefit is reliable, high-speed expansion, allowing seamless integration of essential single slot PCIe cards like capture devices or high-speed storage into Thunderbolt 3 workflows. Setup is generally straightforward plug and play. While the initial cost is premium, users agree the stability and performance gains justify the investment, viewing it as a necessary workhorse. It successfully unlocks desktop level expansion capabilities in a compact external chassis.
Know before you buy
The chassis supports full-height, half-length PCIe cards, such as high-speed RAID controllers, 10GbE network adapters, or professional audio interfaces. It features a PCIe 3.0 x16 slot that operates in x4 mode, which is sufficient for most professional expansion needs.
Yes, the unit provides up to 85W of power delivery to your host computer via the Thunderbolt 3 connection. This is generally enough to charge most modern laptops while they are connected to the dock.
Yes, the Helios 3S includes a dedicated DisplayPort 1.4 port, allowing you to connect a display with up to 8K resolution. This is separate from the Thunderbolt 3 daisy-chaining capabilities.
No, the device is designed for plug-and-play functionality. As long as your operating system is macOS 10.13 or later, or Windows 10/11, it should be recognized automatically once connected.
Yes, the chassis features dual Thunderbolt 3 ports. One port connects to your computer, while the second port allows you to daisy-chain additional Thunderbolt devices, such as external storage or other peripherals.
The Mercury Helios 3S utilizes passive cooling, meaning it does not have an internal fan. This makes it an excellent, silent choice for audio recording environments or quiet studio workspaces.
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$250