- PCI-e ##x does not really matter what the number is as long as it is compatible with the graphics card. Most GPUs are at 16x, but you can always use a PCI-e extender and use PCI-e 1x with a GPU that requires 16x.
- PCI-e transfer rate (the numbers before the x) does not really affect mining speeds.
- Motherboards required to support multiple GPU's need CROSSFIREX(for ATI cards) or SLI(for nVida cards) compatibility, which allows you to use multiple GPUs. I saw that someone post that they mined WITHOUT it, but I rather not question or try that.
- Do not skimp on the power supply. The PSU should be able to support your card(s), roughly, anything worth buying 7950, r9s should use about 200-400watts. PSU efficiency can lower the wattage needed.
- CPU does not really matter, because all of the work will be done with the PSU.
- For super pro-ness, you need to adjust custom drivers and find the most optimal settings for cgiminer
PCI-e version and speed usually does not matter. However be aware that some slots may have
indirect links to the CPU, i.e. with a northbridge in between doing translation and managing peripherals through a few PCI-e lanes. This is more common on Intel platforms. In these situations, you may lose hashrate.
Don't skimp on the PSU, indeed. Consider 200W per 280x or 7950,
minimum and after undervolting the cards. Don't use a PSU at above 80% capacity 24/7 specially at high ambient temperature. Single rail PSUs are easy to work with, multi-rail have some extra precautions but can be a pain in the ass to balance the load. If you can get an EVGA Supernova G2 1300W for a decent price, go for it. Some guys use 2 PSUs per rig, but dual PSU with powered risers is only recomended for experienced miners.
CPU does not matter
for scrypt, that's for sure. I suggest though that you pick a dual-core Sempron 180/190 for $5 more than a Sempron 145 or a PentiumG for Intel platforms. You'll use CGWatcher, Teamviewer, MSI Afterburner, etc... mine coins that need more CPU side validation. That said, I don't really want to argue the point.
Adjusting settings isn't really pro-ness, it's a necessity after you throw 2000€ into hardware and pay 0.1 ~ 0.25€ / KW/h.
- I think you can use multiple types of GPU's to mine? I do not think it matters, they do have to be the same if you are using the GPUs to improve graphics, since SLI/Crossfire doesn't work with different cards. But since we are using the cards to mine, it does not matter. Right? lol
- How the F-, can you calculate how much wattage/Hour or day that are using? I see all these calculators that determine profit, but I do not understand how we can insert wattage into the fields. Like everyone advertises or says that it uses #####w. But does that mean per day? Overall? Hour? Or is it a universal thing I just dont know about?
- Even with optimal cooling, a lot of people are running cards at 100% efficiency, 24/7 foreverrrrrrrrrr, wouldnt the cards be too strained and just die out? Or is there a rest time?
- Should your GPU's fan be at 100% or is lower better? I assume having other things to cool the GPU's and keeping the fan UNDER 100% would make it last longer and lessen the strain. Or is it better for good outside cooling + 100% fan?
- Can you use riser cables with pcie extenders?
- Meh, thats all for now, I thought I had more... But thats it.
You can use multiple types of GPUs to mine, yes. I suggest you stick to R9-270, R9-280 and R9-280x. The R9-290's are harder to mod and undervolt. Sometimes it can be convenient to have a rig with N cards and a half(
), e.g. 4 280x and a single R9-270, due to the PSU you're using. For example, you have enough power for more than 4 280x but you're not comfortable with 5.
To calculate wattage, you get a device like a KillAWatt. Otherwise to get a general idea, use HwInfo software, watch the GPU and VRAM power usage and multiply by ~1.3
Cards WILL get strained and die. The temperature reported by the miner software isn't the only one, VRMs can reach 110ºC and the ram temperature isn't really known. That's why it is MANDATORY to undervolt by modding the bios. There are plenty threads about this, even a famous one by drakoin here on the forum.
The fans shouldn't need to go above 70%. If they do, you need to undervolt more and get better cooling.
Make sure you get those PCI-e powered risers with USB cabling. Connect the videocards, move them away from the motherboard and provide ample ventilation. I suggest the videocard driving the display should be connected on the PCI-e 16x slot, for convenience and stability, but it isn't mandatory to do so.
