I am kinda scared to buy a card just for mining right now, but my plan is to buy every card I need this year (I need a Polaris 11 bad and maybe a 10 if it is better than a 390x at 1080p) as soon as they launch and not sell my old card until mining isn't useful.
I make mining very simple.
If I need to upgrade, AMD upgrade costs X - Y earnings a month, while NV card costs X - either 0 earnings or less than Y earnings a month. In that case, since AMD cards end up costing basically $0 over time and do so faster than Nv cards do, NV cards aren't an option until this changes. It's as objective as it gets. If you can get a free Mercedes, would you pay full price for a BMW?
The poster above me tried to position mining as a 1 way street - investment and tried to calculate that it's impossible to even break even. There is another way to look at it. For example, I had older PC parts and I wanted a full system upgrade. I sold my old parts to get a Skylake 6700K system. That means the $ spent on upgrading doesn't count towards system cost since I was going to do that anyway before my old Sandy Bridge DDR3 didn't dive into the ground with resale. Same with GPUs. Eventually they become outdated and need upgrading. The way I look at it is I will be upgrading no matter what -- so might as well get an AMD card that pays for a fraction of itself or for most of it. I've used this strategy since 2008 with HD4890 and paid $0 for GPU upgrades ever since. Obviously since the payouts are still very good, if I were building a new rig or upgrading, I would go for 2-3 Polaris 10 anyway. This is because they are making $$$ in the same system. For you think one Polaris 10 $299-349 will pay for itself in 6-7 months, then 2-3 Polaris 10 cards will pay for themselves in the same timeframe. The risk is extremely limited since even after 2 months or mining, you are already winning. For Canadians we also get an automatic 27% uplift in currency value. The only questions right now are Polaris 10's price, exact launch date and MH?
Otherwise, come June and it'll be X-Polaris cards XF vs. X-GP104 cards SLI. One makes more money than the other. That means if you buy NV, financially it's even worse. For that reason there is little logic that I've seen thrown around in the last 8 years. It's usually excuses from team green faithful. Their argument is they'd rather pay $1000 GTX580 SLI, $1000 for 680 SLI, then $1400 for 780 SLI then $1300 for 980Ti SLI vs. getting 'equivalent' AMD setups for free ... Because reasons. Start adding up all the GapU upgrade costs every gen, and it turns into thousands, more for multi-GPU setups. Believe me the same arguments we read for the last 8 years, even back when a single 4870/4890 made 0.5-1 bitcoin a day!
Once mining fails, I'll reassess and move on. But until then, every time I upgrade, the NV option is always more $, always.
TL;DF: As long as you are looking at mining as a bonus for planned upgrades in the first place, there is no risk at all. It's essentially AMD vs. NV where one pays for itself far faster. That means if you have 2-3 PCs with older cards that need GPU upgrades, AMD wins automatically. If you are thinking of building 2-3 or more mining systems in hopes to make lots of $, and those rigs were not planned upgrades or you didn't calculate the risks, that's completely different.
Note that I have not build a mining rig but what you forget is that a) for some this is a hobby and hobbies can cost and consume time and might seem idiotic to others (eg the tinkering). The later is why I don't do it plus heat in summer (no AC here...). Plus b) that many of the hard core miners are betting on ETH to rise over time. Be it now or in 5 years. If it takes of like bitcoin and is worth $500 a coin, you suddenly have a huge a mount of money.
Great points. It's like on the CPU sub-forum people who have 2008-2010 rigs are trying to argue that new Intel stuff isn't worth getting since it's too expensive for them. Yet, they don't want to do the work reselling old parts to help them offset the cost. If you don't want to put in the hours into your hobby, it's either not your hobby, or you make so much $, that your time is way more valuable. With PCs, many people upgrade regardless of mining. You can view it as "I want to mine --> need new hardware OR I need new hardware for my PC --> might as well mine on the side for fun when at work/sleep).