GTX 280 cable questions

I just purchased an EVGA GTX 280 and I have some questions about the cables.

First off, in the little Installation Advisory it says don't use the 6-to-8 pin for long periods of time, what can happen ? I probably wont have another PSU for atleast 2 weeks, but hope to get in alot of gaming in the meantime. Will anything go wrong ?

Also, there are 2 connectors on the GFX card, 6 pin and 8 pin, what do I do with these? plug both in? Do I set this up like 2x3 pin connectors into 6 pin connector ( with the adapter) and the 2x6 pin into 8 pin adapter? both adapters in ?

And what do I use the SPDIF GND cable for ?

Thanks for the answers.

Alright thanks, I have a Creative x-fi, so should I use that cable ? also the 6-8 pin thing was the 2 6-pin molex into 1 8-pin molex adapter.

will it be fine if i use these adapters ? it says not to use unless you have too.

alright, thanks alot.

another quick question, ive got my card set up however whenever i turn my comp on with it the screen goes all weird colors. is 2x 12v @ 20A enough?