*Start the video at 9:05 to see the part where I overclock the miners.
In this guide we will focus on how to safely overclock the NewPac USB Miner.
Remember, overclocking the NewPac will void warranty. Overclocking devices generally voids warranty in most manufactures.
Why would you want to overclock the NewPac? well, if you don't you get only about 23 GH/s of mining power. Although it's safest, most efficient way to mine, you might want to overclock it to reach much higher clock speeds and get more from your purchase.
Before we start overcloking, I recommend reading How to setup the GekkoScience NEWPAC USB Miner? first.
Before you even thinking about overcloking, you must provide active cooling for your miners. The NewPac does NOT come with any fan or active cooling, it only comes with a small heatsink.
ACTIVE COOLING - To provide cooling you can use any of the following -
1. Bitcoin Merch® GekkoScience NEWPAC USB Fan Upgrade - This little device was specifically designed (by me) to actively cool the miner efficiently. It works so well that I have reached the higest amount of hashing power using this fan (110 GH/s and up). That's a 300% increase in mining performance than stock.
2. USB Fan ARCTIC Breeze or USB Powered Fan for USB Miners - Those fans work generally for any cooling application where the cooling need is small like the NewPac. The benefit is that they are cheaper, and will work with variety of USB miners. The downside is that if you are using a usb hub, it will take one of your USB slot in order to operate it. It's also not as effective as the first solution.
3. House fan - You CAN use your house fan to cool down your miners but this solution has the most downfalls. It's loud - and it takes allot more power than the USB fans. It also takes allot of space and it's for sure an overkill.
Whichever you choose, make sure you choose one. DO NOT OVERCLOCK without cooling. In minutes the NewPac will overheat in a deadly loop and die forever.
TEMPATURE - The NewPac has two BM1387 chips. You can view the specifications of those chips from BM1387 Bitmain Website. The chips generally run at around 70°C when not overclocked. When you overclock it, it might reach up to 90°C. You don't want to pass above this temperature, so watch it carefully. The lower the better, I aim for 80°C operation temperature or lower during overclocking.
POWER - At stock speeds, the NewPac takes only 2.5W, which most USB ports can handle. But once you aggressively overclock your miners, you will can reach up to 10W - 15W. This is why I recommend the Bitcoin Merch® - 10 Port USB Hub for overclocking. Each port supports up to 12W even when they are all overclocked at the same time. It has a massive 120W 12V 10A power supply included with it.
SETUP - I will be focusing on cgminer setup in this guide. If you know a bit of coding, you can use this guide to other mining software and other operating systems like Linux and Raspberry Pi.
Let's talk about frequency. The expected performance of the NewPac is about 0.228 * MHz = GH.
At the default frequency of 100MHz, the NewPac runs at 22.8 GH.
By increasing the frequency above 100MHz, we are overcloking the NewPac.
Here is an example of the code I use for my setup -
cgminer.exe -o stratum+tcp://pool.ckpool.org:3333 --gekko-newpac-freq 400 --suggest-diff 128 -u 1BURGERAXHH6Yi6LRybRJK7ybEm5m5HwTr -p x 2>%LOGFILE%
Notice in the code "-gekko-newpac-freq 400", for this instance, I have overclocked the miner 4X it's stock speed and achieved 91.2 GH/s of hashing power using the calculation 0.228 * 400 = 91.2 GH/s.
I recommend starting slow. Start by increasing the frequency by 50 at a time, let it run for a few hours and see temps and stability. For example "-gekko-newpac-freq 150". Once a few hours pass, all is good and nothing is overheated, go ahead and increase it another 50 MHz. Do this until you reach your desired hash rate. You will probably hit a wall (and burn your miner) with everything above 400 MHz. I actually don't recommend getting all the way up there for a long periods of time. But the risk is part of the fun (FOR ME!).
Please be careful when overclocking, don't mine on flammable surfaces or put in danger your expensive gaming PC at risk of burning it's USB port, or your motherboard.