FYI, I tried overclocking one of my U1's utilizing the resistor mod... I put a 10K 1% resistor in for R2 and a 3.74K 1% resistor in for R1 (both 0603 size).

Using bfgminer, I'm getting terrible hash rates now (and the unit gets much hotter...) doesn't seem like its doing much/anything. Not sure bfgminer is doing the right thing though, because regardless of what I set --set-device ant miner:clock= to, I can't really get (any of) my units to go above ~1.9Gh/s. Even at what should be higher clock rates, I get a pretty stable 1.9Gh/s and no errors. Any tips?

1/10watt iirc? Shouldn't really matter though, not like much current is going through them...

Miner settings:

bfgminer -S antminer:all --set-device antminer:clock=x0A81 -o [mining pool here]

Tried assorted clock speeds... didn't seem to make a difference. I've reverted to the standard 1K resistor in R1 (R2 open) for now; speeds are back to normal. I might try again once I get a better power and cooling solution setup.

Thanks... I'm working on this during the actual game, watching the commercials :-P

Turns out since I had a .bfgminer.conf file saved, bfgminer was loading the clock speed that I had set there (x0881) instead of the one I was setting via the command line argument.. .*stupid* (even after removing the configuration file, it tried to then read my .cgminer file.. wash't until I removed both that it respected my command line args)

Now that clock speeds are working as expected, I'll definitely be giving the resistor mod another go. Going to make sure I get some better cooling first though

Thanks!

(iluvpcs, apologies for hijacking your thread... hopefully others here find this useful though)

Wish I figured all this out before I attempted my resistor modding... Looks like 3 of my 6 miners currently can do 0x0981 without hw errors, and the other 3 can only do 0x0881 without hw errors.

By specifying hardware paths directly I can get two instances of bfgminer running, each with different clock speeds:

(these paths are for os x):

bfgminer -o [mining pool] -Sdev/cu.SLAB_USBtoUART -Sdev/cu.SLAB_USBtoUART15 -Sdev/cu.SLAB_USBtoUART16 --set-device antminer:clock=x0981
bfgminer -o [mining pool] -Sdev/cu.SLAB_USBtoUART21 -Sdev/cu.SLAB_USBtoUART22 -Sdev/cu.SLAB_USBtoUART23 --set-device antminer:clock=x0881

I'll choose one of my '0981' units when I attempt the resistor mod again... and obviously will sort something out RE cooling too.

Although your settings are indicating a average hash rate of roughly 2.2 GH/s/unit your settings appear to be resulting in a fairly low efficiency (Efficiency defined as number of shares accepted (multiplied by their difficulty) per 2 KB of bandwidth) and a low percentage of accepted shares with a higher number of rejections than I have experienced. Although I readily got 2.2+ out of my U1's, it took some tweaking to actually get my U1's to perform where it counts. There's a difference of about 4+ GH/s there for your six units. That's like canning two units running at stock frequency.

You may want to start by trying to raise your worker difficulty from 8 to something a little higher.

I believe that to be one aspect but also suspect lingering issues with bfgminer and the U1,  at least this I encountered on my pi miner. Hopefully the latest builds have resolved this. I rectified it with updates and ceased updating with 3.9.0 when the problem disappeared.

FWIW I'm averaging 6.75 avg from 3 U1's and slush pool is telling me I'm just shy of 6 which concurs with bfgminer accepted now.

This isn't hijacking. It's a free thread bump.

yeah I paid 0.053 iluvpics 2 weeks ago.

Beastlymac's last U1 shipment was 2 weeks late. Each unit was 0.07 each. By the time they arrived in the US, US suppliers were selling in-hands for 0.053.

He probably won't have the same delays this time around, but that is what happened last time. It hurt me to the tune of $500 as I went in for half on 100 units. The delay was not necessarily his fault, but it did happen and I am not sure what steps are being taken the second time around. Shipping from China to AU to US may just increase the chance of delays. Makes some sense.

I have ordered about 75 each from iluvpcs and Canary and both have been absolutely great for US shipments.

Iluvpcs .... sent you a pm with a question  I would like to order two, see pm sent yesturday