The Cardboard Wonder
A couple of years ago I picked up an AMD Instinct MI25 for cheap on eBay, seemed like a good idea at the time since I wanted to dabble with ROCm and I was doing my Data Science MSc at the time.
I've since replaced it with an Intel Arc A380 since I only really tried using it for hardware accelerated transcoding in PLEX, and later Jellyfin, but it occurred to me that it might be worth sharing the custom shroud I had to make for it way back when I bought it.
I originally had a Tesla K20x but the poor support and low RAM amount prevented me doing anything particularly interesting with it, plus the only way I could cool it was with an ungodly noisy fan&bracket from eBay.
Since they're server grade these GPUs are passively cooled of course, but I didn't have a rackmount server with forced airflow, so I needed a solution to actually cool the card when I was trying to use it.
The AMD engineers were kind enough to leave the fan header from the Vega 56/64 cards populated and electrically connected on the MI25, so attaching a fan to it was as simple as buying a replacement Vega fan on Aliexpress & attaching it to the baseplate with some double sided tape, that's still attached 6 years later.
But since my card came with a proprietary steel shroud I needed a replacement, and a stock Vega 56/64 shroud wouldn't have fit since the heatsink assembly is different for these cards. (If I'm remembering correctly.)
Well I had a lot of cardboard on hand, and some PVA glue...
So I made my own.
I didn't have a dremel at the time so I ended up butchering the IO shield with a pair of pliers to get more airflow through the card, which was probably completely unnecessary in retrospect.
The next issue was that these cards don't have a built in temperature-fan curve, since they're not supposed to have a fan connected to them at all, so the fan wouldn't ramp up under load.
As usual the open-source community is there to save the day and provide tools to alter the fan curve of AMD GPUs that thankfully worked with the MI25's fan controller, probably because it's the same as the Vega cards.
chestm007
So my criminally under-utilised MI25 had a working fan for the duration of its life.
I did eventually try to use it for Ollama LLM models for a Home Assistant voice assistant, but the performance was always very poor, and when I finally moved that server into a proper 3U case there just wasn't room for it in the chassis.
I still have it in a box, and maybe I'll resurrect it someday, maybe that 16GiB for HBM2 will come in handy for something.
Thanks for reading my ramblings if you've gotten this far.
I am trying to get around to writing some more articles, even though I probably don't have anything of value to say.
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