I've tried to look for PCIe x1 GPUs for quite awhile, just something basic that I could shove into an old server and give me a few more display choices (onboard of one server is a little trippy) and not had much luck.
As correctly stated earlier in this thread, there will be no difference in hashrates as the bandwidth of a PCIe x1 slot is more than enough, using PCIe x1 extenders to fit PCIe x16 GPUs works perfectly fine (tried and tested myself)
Cost effective wise, if you're going to use Nvidia cards then don't attempt to mine SHA-256 coins, or even Scrypt coins above a difficulty of like 30 as your hashrates to earnings are almost likely going to be negative if factoring in Electrical and Internet costs.
If, however, you're on a flat rate tariff, whereby you pay a single rate for your electric and it doesn't increase, then mining any GPU (As long as you break even) would be well worth it on any coin.
If you feel daring, or just want to test the water per say. Pickup some of these newer coins floating around, 'funcoin' or not just see how things play out for a bit and see if you want to continue mining seriously.
EDIT:
There's no reason why that motherboard/computer cannot support an ATI card. Such person who told you otherwise either doesn't know what they're talking about or are heavily biased to certain setups and manufacturers.
As long as you have the headroom and ability to power the graphics card from your PSU, you'll be fine.
As correctly stated earlier in this thread, there will be no difference in hashrates as the bandwidth of a PCIe x1 slot is more than enough, using PCIe x1 extenders to fit PCIe x16 GPUs works perfectly fine (tried and tested myself)
Cost effective wise, if you're going to use Nvidia cards then don't attempt to mine SHA-256 coins, or even Scrypt coins above a difficulty of like 30 as your hashrates to earnings are almost likely going to be negative if factoring in Electrical and Internet costs.
If, however, you're on a flat rate tariff, whereby you pay a single rate for your electric and it doesn't increase, then mining any GPU (As long as you break even) would be well worth it on any coin.
If you feel daring, or just want to test the water per say. Pickup some of these newer coins floating around, 'funcoin' or not just see how things play out for a bit and see if you want to continue mining seriously.
EDIT:
There's no reason why that motherboard/computer cannot support an ATI card. Such person who told you otherwise either doesn't know what they're talking about or are heavily biased to certain setups and manufacturers.
As long as you have the headroom and ability to power the graphics card from your PSU, you'll be fine.