u/esw123

Added 3rd GPU and now getting VGA error LED on motherboard. 99% seems riser fault cause it isn't working with any GPU in any slot even when one GPU connected but maybe anybody had something similar with Gigabyte B850 motherboards? PCIe 3.0 x16 30cm riser. Everything was powered on, photo was done before connecting power cable.

Reordered 4.0 20cm.

Thanks to the community help I finally launched this llm. LM Studio refused to load weight onto second GPU but Unsloth Studio did so everything was done in there. Not a proper benchmark (used PC in parallel as well) but it gives an idea of ​​the performance from dual 3060 with RAM offloading.

DeepSeek V4 Flash 0731 IQ2_M from Unsloth

CPU: Ryzen 7500F
GPU 0 (PCIe 5.0x16 lane): RTX3060
GPU 1 (PCIe 3.0x1 lane): RTX3060
RAM: 96GB 5600

Prompt: Write me a tetris game.

Result (copy from the summary):
Prompt eval: 2.96s
Prompt speed: 3.0 tok/s
Generation: 960.02s
Speed: 4.5 tok/s (PowerShell shows 3.5 tok/s, don't know why it shows 4.5 tok/s, single GPU with RAM offload output was around 3 tok/s so I trust PowerShell metrics more)
Tokens: 4,338
First token: 2.96s
Cache hits: 1
Total: 963.32s
Chunks: 4318

Wattmeter is on the way but my estimate is around 130W total system power draw (with 2 monitors connected but they are not taken into account) Each GPU used 30-40W with 0.9V undervolt. Task took around 16 minutes to complete, consumed around 35 watts and cost 0.0059 euros.

Update:
OS Windows 11.

Actually math is showing 4338/960.02=4.52 tok/s, don't know why PowerShell showed 3.5 most of the time. I ran one more request with web search and it gave 4.7 tok/s. Updated 3.5 -> 4.5 tok/s.

I want to try unsloth studio but can not initiate installation already, how to fix this:

Using this tutorial: https://unsloth.ai/docs/new/studio/install#windows

PS C:\WINDOWS\system32> irm https://unsloth.ai/install.ps1 | iex

  🦥 Unsloth Studio Installer (Windows)
  ────────────────────────────────────────────────────

  winget         available
  python         Python 3.13 already installed
                 preserving existing environment for rollback...
                 previous environment preserved for rollback
  venv           creating Python 3.13 virtual environment
                 C:\Users\___\.unsloth\studio\unsloth_studio
  gpu            NVIDIA GPU detected
                 installing PyTorch (https://download.pytorch.org/whl/cu130)...
                 installing unsloth (this may take a few minutes)...
  unsloth        2026.7.6 installed
  setup          running unsloth studio setup...
Refusing to run Unsloth inside System32 as it will lead to Errors.
cd to a normal working directory and try again.
[ERROR] unsloth studio setup failed (exit code 1)
                 restoring previous environment after failed install...
                 restored previous environment
unsloth studio setup failed (exit code 1)
At line:153 char:9
+         throw $Message
+         ~~~~~~~~~~~~~~
    + CategoryInfo          : OperationStopped: (unsloth studio ...d (exit code 1):String) [], RuntimeException
    + FullyQualifiedErrorId : unsloth studio setup failed (exit code 1)

I had one RTX3060 and was able to use all models like Qwen3.6 27B, Qwen3.6 35B and Qwen3.5 122B with CPU offload. I've added second 3060 and now only dense model can be loaded as usual, 35B loaded only once and 122B refuses to load at all. What setting should I change or where to look for potential problem solving solutions?

Update: Seems 12 layers in VRAM is the limit for dual 3060 with qwen3.5-122b-a10b. Reduced to 12 and model loaded. 35b-a3b loaded as well after PC restart and when I changed GPU priority back to 3060 installed in PCIe 5.0x16 from the second GPU installed in PCIe 3.0 x1 (deviceID: 1 and then deviceID: 0).

I have only 12GB VRAM (RTX3060) but have enough RAM to run Qwen3.6 27B Q4 with offload. Something tells me that it won't achieve maximum performance but why DRAM speed is only around 30GB/s (HWiNFO data) during inference with dual channel 5200 RAM? TG is 3.12 tok/sec with 18K tokens result.

I expected slow speed, but can't understand where is the bottleneck, is it how LM Studio works or I need better CPU (I have 7500F). Of course dual 3090 will do the work, but it is what is for now.

Tried smaller prompt with 6 CPU threads, Q8 KV cache, 37 GPU offload, got TG 4.95 tok/sec and bandwidth was 30-35GB/s.