i would also suggest using a linux based mining OS....there are several really good one
mmpOS (rig up to 8 gpus free forever)
hiveOS
Smos
Raveos
I know some allow free 30 days or some have other trial or even free cost for small miner. I would say try them and see which one you like best...
They will be way better on older hardware then windows....and more stable.
Most are small enough to run off 16gb thumbdrive or small ssd or even old hd...but thumbdrive is lowest power
And please pay attention to power draw... a GPU can pull a surprising amount of power and if you dont respect the power draw its easy to get the 🔥
Best to power the riser (little pcb that the gpu will plug into) with a 6pin PCIe just like is found on graphics card. Really only the Molex (4 pin in row) has enough power to be safe. Sata to 6 pin is asking for trouble especially with higher wattage cards.
Always power a gpu and its riser from the same PSU if you end up with multiples. And dont expect much from the stock psu...it was not designed to put out that many whats..and problably doesnt have that many 6 or 8 pin pcie plugs. I use 1200 - 2600watt psu’s on my rigs. Ive got a couple with just 4 cards and use 1000w on those. And currently PSUs are like every other part of a mining rig...expensive and in short supply.
The riser to main board uses a usb cable (comes with the risers) and a small edge card. Why the cable and connections are usb in shape they are not in signal. This is actually just a way to use commodity connection to link the gpu to the card slot so data flows.
Im sure you will have plenty more to discover. I suggest watching videos of folks building rigs on youtube and read everything you can on mining rigs. And make use of the (Search) of the forums for answers...and of course ask questions. There are folks here who have forgotten more about gpu mining then ill ever know
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