Quote from: Trongersoll on September 12, 2013, 04:10:32 PM

Quote from: mjgraham on September 12, 2013, 01:52:46 AM

My latest incarnation, decided to build a circuit board, plus as USB hub controller plus an aftermarket dc-dc , working the speed back up, I have found the problem that is causing my high speed issues seems to be ground loops, I guess it is to be expected with so many random parts in play. seems to be on the USB side I guess the long cable to the raspi that has a ground too. looks neat but doesn't work as well as I had hoped. I actually had all these parts already for many projects in the past. Have a single clock with a fanout buffer to the others. Plus all the work involved for such little gain really it changed it from ROI (just for the BE) in 100 days to like 70 ad the price I paid for them, buy then may not even do that. I think the best plan is to use the 16 Mhz and the resistor change far cheaper and effective. If I could get them to go to 28 Mhz would be lie having 7 for the price of 3 might be OK but I don't think I'll make it. As a friend of mine said "your pushing the limits of man and machine"

I would elevate you base heatsink a bit to get better air flow. maybe with pencils or something.

That is a good idea, I'll try that, amazingly the top heatsink is the one that is getting the hottest right now, I am having some troubles with the middle one getting more errors, I think my top mounting arangement is causing a high spot over the top one, I am going to go back and use thermal pads on the top, I basically used a small 3/8" square x1/8" piece of aluminum on top of all the BE100s to space it up tall enough to mount the top heatsink on and clear everything. If I put to much pressure on them they get detected as different devices or go away, I guess I am shorting some signals on the bottom. I am not sure why the top one got 40 PH/s must have been really fast

Quote from: mbbc on September 12, 2013, 06:40:35 PM

Quote from: mjgraham on September 12, 2013, 01:52:46 AM

...plus as USB hub controller...

What controller IC are you using?

Some old TI TUSB2046B's just full speed only but that is enough