Mining on mobile devices in general is a bad idea. They simply do not have the processing power to make things worthwhile. You are likely to never make enough to achieve the minimum payout amount on any pool you join.

You realize that 2020 is less than 6 years away?

The vast majority of the change in the exchange rate USD <-> BTC will come from the change in value of BTC at least in the near future.

And with all enthusiasms let us not forget that despite widespread acceptance Bitcoin are still inherently far more risky than dollars. The chances of bitcoin collapsing in the next 6 years are far greater than that of US dollars becoming completely worthless.

This is why investing in BTC can still give you such high returns if everything works. High risk = high returns, low risks = low returns. This is the rule for investing in just about anything.

Bitminter has recently had some very bad luck with blocks and they mined for over 34 hours on a single block yesterday. maybe that was the reason you did not get any returns from Bitminter because nobody got any for over a day.

Rule of thumb:

If someone is selling you hardware or a contract or some other opportunity to mine coins they are either deeply stupid or they expect to make more money selling to you than they could mining themselves.

Really, if it was profitable to mine for them they likely wouldn't be selling to you.

Also it probably won't save you much in the way of costs I can tell you that you don't really need a monitor or usb keyboard and mouse with the Raspberry Pi.

I managed to get mine set up without ever connecting it to a screen or input devices. It wasn't too hard.

You can download a linux distro like minepeon onto the SD card on your PC and mange it entirely over the net. If you don't like MinePeons web interface you can also administer it with Putty over SSH which is likely enabled by default in whatever distro you choose.

You don't really need 4 PCIe x16 slots on your mainboard to connect 4 GPUs for mining.

PCIe is designed in such a way as to allow cards with big connectors like graphics cards which typically feature x16 connectors with less lanes like x8 or x4 or even only x1.

If you were wanting to play games or other actually graphic intensive stuff on your computer you would need the bandwith that comes with a proper PCIe x16 connection. For mining a PCIe x1 connection is sufficent since only a limited amount of data is tranferred back and forth on the PCIe bus.

So if your mainboard has 4 different PCIe slots you can in theory connect 4 different PCIe x16 cards to them and have them work fine for mining.

The only problem is making them fit. Physically cutting down on the connectors to make them fir is theoretically possible but practically a really bad idea.

There are PCIe risers that can help you with the problem of physically getting your cards to fit on the board. There are even PCIe risers that function as splitters and turn a single x16 slot into 4 x4 slots for example.

As far as the PCIe Bus is concerned the whole thing would not be a problem. However you still need a to power and cool the whole thing and that is more likely to end up being trouble.

It is not the speed alone that is the problem. you can buy the fastest miner available and still not make any money as long as you pay more for it than you are likely to get back out. Block Erupters and REd/Blue Furies tend to sell for more money than you will be able to make with them on places like ebay.

I don't think I have heard of any cryptocoin other than bitcoin being used for anything other than trading it for bitcoin or real money. I certainly have never seen any shops advertising the fact that they accept payment in litecoin or dogecoin.

I don't think that trying to mine Bitcoin at all with just those these two CPUs can be recommended regardless of pool.

Do you have any graphic cards in these machines or just the onboard graphics?

PCIe is designed so that in theory basically any device can connect via any number of lanes with the bandwidth limited by whatever is lowest.

You can put an x1 Card in an x16 slot and it will work fine and you can put an x16 card into a slot that only has 8, 4 or 1 lanes and it will work albeit with only half, a quarter or a sixteenth of the bandwidth. In theory you could file open the end of the slow to allow cards with longer connectors in shorter slots but a riser seems like a smarter idea in practice.

Many motherboards have a second x16 slot that actually only works with 8 lanes and only is x16 in length so that people can put larger cards in there without having to file anything down.

Generally the number of lanes in total even with risers is limited by the PCIe controller which in modern computers is in the CPU and in slightly older ones in the chipset. Even server level Intel Xeon CPUs only provide 40 lanes worth of PCIe per CPU.

It should be noted that you don't even have a cheap dedicated  GPU but just the Intel graphics processor integrated into the CPU. It won't give you much in the way of processing power. Even if you had bought a good notebook with switchable graphics it would be a bad idea to mine with it, since notebooks really aren't build to run under full load for extended periods. You will run into overheating problems and ruin your laptop if you try to let it run 24/7.

I didn't know there were any sites like this.

Is there a list somewhere of non-scam websites with similar schemes?

If you want to hedge your investment against the chance that the whole bitcoin thing might collapse into itself, I don't think any altcoins will do you any good.

Almost all the value in the alt coins is in comparisons to bitcoin. There might be fluctuations in the exchange rate that you can use to make money trading back and forth, but as it is right now only bitcoins has any real non speculation based value.

There aren't many shops in the real world that accept litecoins or dogecoins to pay for pizzas or sports cars.