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#11
You can easily obtain the required converter leads from Amazon or a similar supplier. If the GPU draws too much current then the PSU should shut down causing failure to boot or a BSOD.
Your PSU appears to be very old. It may be time to buy a new good quality branded PSU. I would buy a PSU having a minimum 750W output. You can uses an online PSU calculator to work out what power you need. I currently use EVGA PSUs due to the 10 year guarantee.