SERIOUS cooling for Antminer U1

[phoenixsilverbird]

Alright, so I have my antminer U1s (3 of them) overclocked to 2 GH/s each on a D-Link 7 powered hub connected to rpi running cgminer.

I plan to overclock to 4GH/s but , before I do that, I need to find a way to cool these. I am already using a Coolerguys 120mm USB fan, but the antminers are still getting too hot to touch even at 2GH if you touch them for a few seconds.

What should I do? Can these Antminer U1 (NOT S1) be water cooled, or should I buy more fans..?

[phoenixsilverbird]

I've bumped this thread 3-4 times now and deleted my own bump replies to avoid spam.

I need some help, please people! 

[Walking Glitch]

BEs are fine if they are to hot to touch for half a second, let alone a few seconds, and these should be too. You could likely hit 2.2GHs without any modifications. If you want to OC further, you will need to replace a pair of resistors, and add a heatsink to the back of the board, which would probably let you hit 3-3.4GHs depending on how much airflow, and how good the chips are.

[crazyates]

I saw a guy that was submerging his BE in a small jar of mineral oil, and it was quite a bit cooler. You could look into that?

[HellDiverUK]

I guess you could remove the metal plate on the back, and use the bolts to bolt the U1 to a decent heat sink - like an old PC heat sink, or a big lump of aluminium our of a power amp or similar.  You'd need a heap of short USB extension cables, though.

I have ten of them in a Anker hub, all doing 2GH, with only a 140mm fan blowing across them.  

[phoenixsilverbird]

The Antminer U1 user manual provides no instruction or information on replacing any components.
On a picture it circles two resistors and leaves it at that!

I do have a list of bmsc freqs going up to 4 gh.

Also, is a heatsink necessary?

[HellDiverUK]

The Antminer U1 user manual provides no instruction or information on replacing any components.
On a picture it circles two resistors and leaves it at that!

If you need any more information than that, then you shouldn't be doing the mods.

Also, is a heatsink necessary?

The metal backplate is a heat sink.  If you're overclocking more, then you need a bigger/better one.  2GH is about the limit of the supplied heat sink.

[Walking Glitch]

These dissipate heat from both the front and back. Zip-tying a small aluminum heatsink (chipset sinks anyone?) to the back with some thermal grease, or skipping the zip ties and using a thermal pad would probably allow you to hit 3-3.4GHs with a fan pointed at it. Thing is, you have a limit of 2.2GHs without replacing those resistors, which, if you need more information to figure it out than what the user guide supplies, you really shouldn't be trying to mod them, as you WILL break it if you try.

[ninjaboon]

I saw a guy that was submerging his BE in a small jar of mineral oil, and it was quite a bit cooler. You could look into that?

quite cool, maybe I will try on 1 unit U1 later

[NecroBones]

Thing is, you have a limit of 2.2GHs without replacing those resistors

So, if you want 2.0 - 2.2 GH/s, just simply changing the clock settings is sufficient? That's good to know.

[HellDiverUK]

Thing is, you have a limit of 2.2GHs without replacing those resistors

So, if you want 2.0 - 2.2 GH/s, just simply changing the clock settings is sufficient? That's good to know.

Yeah, mine run at 2.2GH not too bad at stock volts.  One out of the 10 is a big high in the HW errors, but still below 5%.

[chadgroover]

What's the frequency for 2.2GH/s? For some reason I thought 0981(2GH/s) was the limit without modifications...
Logically I would assume 1081, but these things aren't always logical!!

Mine are cool as a cucumber at 2, so I might as well push them a bit harder!

[U1TRA_L0RD]

Cant you use thermal paste and then put the sink back on?

[PaintShopPro6]

Make sure to check your pool performance if you are overclocking to 2.2 GH without replacing resistors.

One of my 6 Units will show the full 2.2 GH/s in CGMiner, but my pools will only show about 800 MH/s for that unit.

While viewing the local hash rate is useful, make sure to confirm the number with your pool.

In my experience (low sample size), some units are happy at 2.2, some at 2.0.

Good luck!

[philipma1957]

What's the frequency for 2.2GH/s? For some reason I thought 0981(2GH/s) was the limit without modifications...
Logically I would assume 1081, but these things aren't always logical!!

Mine are cool as a cucumber at 2, so I might as well push them a bit harder!

0a81  is 2.2 most of my sticks prefer 0981 only a few do well at 0a81

[cyberm]

how about using the peltier effect: http://en.wikipedia.org/wiki/Thermoelectric_cooling

not sure if it will keep your rig moneymaking, but should be fun to do it

[Gator-hex]

I don't know what fans the Antminer uses but there are some seriously fast fans out there.

You need to look for higher CFM to move more air faster over the cooling surfaces.

Also try and build a wind tunnel so it enters one side and exits the other.

I was recently supplied with Sunon 4.7W 4500RPM 75CFM on a Hex16B miner

http://www.alliedelec.com/search/productdetail.aspx?SKU=70226025

They are insane but there are even faster ones available from this supplier!

[HellDiverUK]

I don't know what fans the Antminer uses but there are some seriously fast fans out there.

The U1 has no fan.  You're thinking about the S1.

[Gator-hex]

I don't know what fans the Antminer uses but there are some seriously fast fans out there.

The U1 has no fan.  You're thinking about the S1.

Advice still stands though, larger surface area via heatsinks, and/or more air passing over the surface via a faster CFM rated fan.

Another option is run your stuff in a tank of mineral oil and pump that through a radiator with fans blowing through them.  

Some seriously insane liquid cooling... http://bitell.sinaapp.com/show.php?tid=938

..but you can do it on a smaller scale at home in a fish tank with PC radiator/pump/fans.

[Gator-hex]

Also you might like to try something like this...

Coolermaster ARC-U01 RAM Chip Cooler
http://www.ebay.com/itm/Coolermaster-ARC-U01-RAM-Chip-Cooler-/181206266073?pt=US_CPU_Fans_Heatsinks&hash=item2a30bc30d9