CPU and the amount of memory for a mining rig?

[IITravel01]

I've got a few video cards laying around and wanted to try to put together a mining rig for bitcoin.  This would be a first for me, I've always just bought Bitmain miners, but why not if I've got most of the equipment and can afford a few hundred to try.
I see that MSI has a Z370-A Pro is only $100 after $10 MIR that's designed for mining.
The only other thing I would need is a CPU, but have no idea which one is recommended or if a minimum is required.  I know the graphics card does the load, but if I've got 8 cards running (2 on motherboard and 6 on riser cards), do I need an adequate CPU to handle the load?  With the Z370 it needs to be a 8th gen. Intel.  Will a i5 8400 65W be OK, it's $200?
I've got the rest of the big items.  A couple 8GB sticks of DDR4 (should I use both or just one)? A CPU Cooler. A few Hard Drives lying around.
I've got a EVGA 1600w Platinum power supply that i'm not using. (will this handle 8 GPU cards?)
I see a case is $60 on eBay https://www.ebay.com/i/322581889838?chn=ps&dispctrl=1 if I need to go with one.
And the riser card set for 6 is like around $45 and the USB 3.0 card is $30 on amazon.com are the accessories I'd need.

[1714795169]

1714795169

[bigjee]

video cards dont mine bitcoin. I suggest doing more research before you order your first part.

[jillscarbrough]

video cards dont mine bitcoin. I suggest doing more research before you order your first part.

He says he will put his GPU rig along with the ASIC Miner (Antminer I think)

I've got a few video cards laying around and wanted to try to put together a mining rig for bitcoin.  This would be a first for me, I've always just bought Bitmain miners, but why not if I've got most of the equipment and can afford a few hundred to try.
I see that MSI has a Z370-A Pro is only $100 after $10 MIR that's designed for mining.
The only other thing I would need is a CPU, but have no idea which one is recommended or if a minimum is required.  I know the graphics card does the load, but if I've got 8 cards running (2 on motherboard and 6 on riser cards), do I need an adequate CPU to handle the load?  With the Z370 it needs to be a 8th gen. Intel.  Will a i5 8400 65W be OK, it's $200?
I've got the rest of the big items.  A couple 8GB sticks of DDR4 (should I use both or just one)? A CPU Cooler. A few Hard Drives lying around.
I've got a EVGA 1600w Platinum power supply that i'm not using. (will this handle 8 GPU cards?)
I see a case is $60 on eBay https://www.ebay.com/i/322581889838?chn=ps&dispctrl=1 if I need to go with one.
And the riser card set for 6 is like around $45 and the USB 3.0 card is $30 on amazon.com are the accessories I'd need.

don't ever pair your gpu on your motherboard. while doing the mining process, all parts of your gpu will increase its temperature and it will melt the pcie socket on your motherboard.

[Deathwing]

CPU Usage will heavily rely on the algorithm you are trying to mine, second, Bitcoin mining with GPU's are worthless. You will not earn a dollar in the next several years.

4 to 8 GB RAM will be ideal in general, one stick is enough.

For CPU, an i3 lineup CPU should be enough but as I said, depends on the algorithm.

[shibob]

You dont need to pay that much for Z370 MB + i5 8400 CPU, also a lot of miners suggest MSI MB is not a good deal. 8Gb RAM is enough, no need to use 16Gb.
Ofc, EVGA 1600w PSU platinum is one of the best PSU, so which GPU you're using? If the GPU's TDP is about 180W, I think it not a good idea to handle these 8GPUs (8*180 = 1440W, risers+cpu+mb consumes ~150W) with 1600w PSU.   

[wacko]

z370 boards are still overpriced, stick to the previous gen (z270/h270). 8th gen CPUs are also more expensive and not worth it for a mining rig.

[beachbummer]

don't ever pair your gpu on your motherboard. while doing the mining process, all parts of your gpu will increase its temperature and it will melt the pcie socket on your motherboard.

Has this ever happened before? First time I am hearing about this possibility...

I have a pair of GPUs on the mobo and they are alright so far.

[jillscarbrough]

don't ever pair your gpu on your motherboard. while doing the mining process, all parts of your gpu will increase its temperature and it will melt the pcie socket on your motherboard.

Has this ever happened before? First time I am hearing about this possibility...

I have a pair of GPUs on the mobo and they are alright so far.

Yes, will be better if you are using PCIe Riser.

[szafa]

What gpu you have?

[DevelopmentBank]

To add to what others have said, i suggest you instead mine Ethereum since it is best for most GPUs. If you want bitcoin, then just sell your mined ethereum in exchange for bitcoin. As you mentioned, your 1600W PSU will be able to power a number of GPUs depending on their power consumption. You need to check the specs of the GPUs you will be buying.

[wacko]

don't ever pair your gpu on your motherboard. while doing the mining process, all parts of your gpu will increase its temperature and it will melt the pcie socket on your motherboard.

Has this ever happened before? First time I am hearing about this possibility...

I have a pair of GPUs on the mobo and they are alright so far.

Nope, that never happens unless some parts are defective. All motherboards with 2+ pci-e full size slots are obviously designed to run with 2 (or even 3) cards installed directly into them (with SLi/Crossfire use in mind). The problems with connecting multiple GPUs to the motherboard directly usually start when you go overboard, like when you manage to connect 4 power hungry cards, for example. And it's not the PCI-s slots that melt, it's the 24-pin power connector. Used to be a common problem back in the day when ribbon non-powered risers were used, I've managed to burn one of my boards' 24-pin connector myself.

[IITravel01]

Thanks for the input.  Perhaps Ethereum might be a better choice.  As for the power supply, I've also got an extra EVGA 1300 G2, so it's probably better to have each handle 1/2 the load.  I don't see $100 for a motherboard as too expensive.  So my question would be for mining Ethereum, is it CPU intensive?  Is a i5 8400 good or is it better to go higher or lower?

[wacko]

So my question would be for mining Ethereum, is it CPU intensive?  Is a i5 8400 good or is it better to go higher or lower?

None of the current gpu mineable algos are cpu intensive, there's absolutely zero difference between i5 and the cheapest celeron for Ethereum mining. Sometimes (very rarely) a new coin shows up with a completely new algo, and the very first miners for that coin might not yet be optimized so people with higher-end CPUs might have an advantage for a very short period of time (before a properly written miner shows up). I think the last time it happened it was sibcoin (not 100% sure). Then again, you'd probably want more than 4 threads for those poorly written miners (8+). These situations are so rare and you're most likely not even gonna hear about those coins well until they've matured and there are no high cpu load issues with the miners anymore, so it's just not worth it to bother with any of this stuff. Most people use low-end cpus in their rigs and do just fine. I've got both two-thread cpus (celeron g3900/3930), 2core/4thread cpus (g4560) and even 4core/8thread i7-6700 in one of the rigs — no noticeable difference between any of these.

[terr281]

I am in a very similar situation to you (the OP), but I immediately began with the idea of using NiceHash to sell hashing power and get paid in Bitcoin.  With a many year history of building (non SLI/CF) gaming rigs for friends and family (usually on 2-3 year GPU and 3-5 year CPU/platform upgrade cycles), and having a pile of leftover parts... many were good enough for the task.  As such, rigs that I now have running (all using Windows OSs):

1. Intel i5 7500, H270, 2x8GB DDR4, (1x) Nvidia 1060 6GB
2. Intel i3 4160, Z97, 2x8GB DDR3, (1x) Nvidia 1060 6GB
3. AMD FX 8320, 970/950SB, 2x8GB DDR3, (1x) Nvidia 1060 6GB
4. AMD Phenom 2 720 BE, 770, 4x2GB DDR3, (1x) AMD R9 270X 4GB
5. Intel Core 2 Duo e6750, P45, 4x1GB DDR2, (1x) AMD R9 270 2GB

6. (Waiting on full part availability for system, including RMAs) AMD Phenom 2 720 BE, 770, 2x8GB DDR3, ?

In the end, the GPUs are the only thing that truly matters.  (As for my setup, it is highly inefficient based upon electric & cooling cost to hashing power.  However, it is winter where I live, and the extra heat of the systems is being used... to heat.  In summer, the lower quality rigs will likely be shutdown.)

[baga105]

I always buy Intel Pentium for my mining rigs since i am not mining with CPU.. Better to spend some more $ on GPUs than on CPU in my opinion