Searching for specific ASIC miner

Hey folks, hope you're doing well. I'm on the hunt for info about ASIC miners (not the home ones) that have been optimized for lower power usage. I can't seem to find the thread where someone mentioned reducing an S19 to 70TH and cutting down its power consumption, even if it's an older model. I'm open to any ASIC miners. So, why am I asking? A buddy of mine reached out, and he's looking for a more affordable ASIC miner that still packs a decent hashrate but doesn't use over 3000 watts. I swear I've seen a thread about this before, but I can't track it down. I think philipma had worked on something similar before, modifying the PSU.

This issue can't be resolved by modifying the power supply. Download the VNISH firmware for the S19 90-95 TH/s and select the 70-80 TH/s operating mode with a power consumption of 1800-2200 W. You can also remove one ASIC board. The downside of the VNISH firmware is the mining fee. You pay part of the reward to the owner of the firmware. Another option is to buy an Epic ASIC controller. https://bitcointalk.org/index.php?topic=5568422

If your friend wants an S19-ish box doing roughly 70TH without drinking 3kW, the trick is usually underclocking and undervolting with aftermarket firmware. That's where people get those "old miner, much lower power" setups from. On these units, efficiency tuning matters a lot more than brute forcing the power supply. PSU mods get talked about like wizardry, but most of the time the real win is at the control and tuning layer, not with a screwdriver and a prayer. For that target, I'd be looking at S19 variants that are known to behave well when tuned down, then run VNISH or similar and aim for the efficient part of the curve instead of maximum TH. That's the sweet spot. Once you start chasing cheap stuff with high hashrate and low watts all at once, physics starts charging extra. You can absolutely make an older unit behave better, but you're not turning a brick into a hummingbird. Sometimes the best deal is actually a slightly better miner run gently, not the cheapest one run like it owes rent.

Used ASIC prices in Russia for today "S19 90th - $90 S19 95th - $95 S19j Pro 104th - $160 S19k Pro 120th - $280" The Bitmain Antminer S19k Pro is a good ASIC, but the problem is that it costs three times more than the S19 90th. Perhaps the price ratios in your mining market are different. For Solo mining, a difference of 10 terahashes isn't that significant.

I don't think modifying the PSU would reduce the power consumption of the unit; you might be talking about underclocking the unit using custom or modded firmwares like Vnish or Braiins OS (as suggested above) or upgrading to an Epic controller; this is mostly what Philipma mentions everywhere to have full control over/underclocking the unit. Or if you are looking for unit that consume lower than 3000watts try using this tool https://www.asicminervalue.com/ Then filter them with only bitmain units and sort them to easily find those units with low consumption. Currently, the best units I could find are the S19k Pro and the S19j Pro (slightly higher consumption), but you can run them with low power mode.

Bitmain has already implemented several operating modes into its ASIC firmware, depending on power consumption. If Bitmain implements the ability to use one or two boards, their ASICs will be in high demand on the secondary market for solo mining. Older Bitmain ASICs allowed mining on a single board, but this option was later removed.

You may be thinking about underclocking or undervolting an S19. Some people run them around 70TH to reduce power draw, but it depends on firmware, PSU, cooling, and chip quality. It can work, but I would not call it a magic fix. Lower watts usually means lower hashrate too, so the real thing to check is efficiency, not just power draw. Your friend should also be careful with modified units. They can be cheaper, but bad firmware or poor PSU work can cause instability.

Only miners with free or very cheap electricity buy the S19 ASIC. In Russia, these ASICs cost $100-$120 and are used in stock setups after cleaning. Some miners use them solo, but that's very rare. Usually, you can buy such an ASIC with the VNISH firmware already installed, because the factory firmware there is very bad.

buy the s19 and go to my signature below buy an epic controller pull the controller and clock away. many options disable 1 board go full speed on two boards or disable two boards go full speed on one board. two boards full speed 2k-watts one board full speed 1k-watt but a bit loud since you did not under clock you have options to under set freq you have options to under set freq you can set fans as low as 25% you can use epic controllers on s19 and t21 and s21 the epic is fee free and gives almost perfect control options over the s19 i use it with  s19 t21 all good

Hi, please can you tell the hashrate that you can get on s19 after disabling two boards? To be precise, what hashrate can you get using 1000watts on s19? I want to see if it's worth the controller swapping. Thanks.

The control board and cooling fans themselves consume around 80-120 watts. If you have a total power limit of 1000 watts from the wall, that leaves around 900 watts for the hash board chips, resulting in a hash rate of around 26-30 TH/s. This is a related topic; similar questions have already been discussed. https://bitcointalk.org/index.php?topic=5463805.0