I bought Radeon 5750 GCU and as I tried to assemble my new computer, I found that I had a problem, since my power supply doesn't have a 6 pin 75W output.
In the requirements for this GCU it is said that the power supply is recommended.
Can I operate my computer without connecting power to the GCU (and of course while keeping my GCU unburnt)?
It will use about 75w, which can be supplied by the PCI slot, at its very limit. If it works, I still wouldn't recommend it. You can buy a $3 converter that will turn one of your 4pin Molex connections into a 6pin PCI connection.
Unfortunately, all the stores are already closed, and will be until the beginning of next week.
If I understood the answer correctly, I will be able to use my new computer for the weekend, but running high performance graphics during this time is very much not recommended.