2018 15" Dell XPS 15 9575 (VegaMGL) [8th,4C,G] + RTX 3090 @ 32Gbps-TB3 (Razer Co...
Clear all

2018 15" Dell XPS 15 9575 (VegaMGL) [8th,4C,G] + RTX 3090 @ 32Gbps-TB3 (Razer Core X) + Win10  


New Member
Joined: 4 years ago

System specs

  • MODEL: 2018 Dell XPS 15 9575 2-in-1
  • DISPLAY: 15.6" IPS 1920x1080 Touch
  • CPU: Intel Core I7-8705G CPU @ 3.10GHz (-0.160V Undervolted, Turbo Boost Off)
  • VIDEO: AMD Radeon™ RX Vega M GL (4GB HMB2 Graphics Memory)
  • RAM: 16GB Dual Channel DDR4 @ 1197MHz (up to 2400MHz)
  • SSD: 256GB M.2 PCIe NVMe
  • THUNDERBOLT: 2 x 32Gbps Thunderbolt 3
  • BIOS: 1.10.0
  • OS: Windows 10 Home 64-bit 20H2


  • EXTERNAL DISPLAY: 1920x1080 @ 60Hz


eGPU hardware

  • ENCLOSURE: Razer Core X
  • CABLE: Razer Stock TB3 Cable
  • EXTERNAL GPU: GigaByte GeForce RTX 3090 TURBO @ 1‎695MHz [2x8pin Power Connector] (GV-N3090TURBO-24GD)
  • BIOS:
  • DRIVER: NVIDIA 457.51


Hardware pictures

Razer Core X with RTX 3090:




Windows 10:


Installation steps

  1. Inserted card and connected 2x8pin power cables.
  2. Updated OS and Thunderbolt drivers to latest, plugged in enclosure and installed the latest Nvidia driver, everything worked plug-n-play.




  • Undervolted CPU @ 3.10GHz
  • Disabled Turbo Bust
  • External 1920x1080 @ 60Hz Display
  • 24C Ambient Temp
  • Closed Razer Core X





2018 15" Dell XPS 15 9575 (VegaMGL) [8th,4C,G] + RTX 3090 @ 32Gbps-TB3 (Razer Core X) + Win10 [build link]  

aurelius pontius, mr.ribeiro, itsage and 1 people liked
Founder Admin
Joined: 6 years ago

@romchu, Thank you for sharing this build. To confirm these performance results were done through the external monitor? They are lower than I expected for RTX 3090 eGPU. Can you try disable the RX Vega M GL dGPU and internal display to see if there's improvement?


LinkedIn | Youtube | Instagram
external graphics card builds
best laptops for external GPU
eGPU enclosure buyer's guide

2021 Gigabyte Z590i Vision D [11th,6C] + RTX 3060 Ti @ 32Gbps-TB4 (Gigabyte Gaming Box) + Win11 [build link]  

New Member
Joined: 4 years ago

@itsage, yes, all benchmarks done through the external 1920x1080 @ 60Hz monitor. Vega is off in Device Manager. I believe the CPU is bottlenecking. If you see CPU score in 3DMark is kinda low but GPU score is okay for 3090 through TB3.


2018 15" Dell XPS 15 9575 (VegaMGL) [8th,4C,G] + RTX 3090 @ 32Gbps-TB3 (Razer Core X) + Win10 [build link]  

itsage liked
New Member
Joined: 2 years ago

Thanks for sharing the build. I was worried that the psu inside the core might not be sufficient for the card so to bottleneck. Can you check whether the card is running on a lower wattage so the performance might be able to jump even higher? My 3070 running on a 3440x1440 for 3DMark Timy Spy is only around 7000 points, given the resolution and card difference, that now seems to be reasonable... 

To do: Create my signature with system and expected eGPU configuration information to give context to my posts. I have no builds.