Just bought a new quad core PC which is great but I want to upgrade the graphics card. Only problem is that my graphics card has a 6 pin PCI Express power connector but there isn't a 6 pin cable attached to the psu.

If I buy a LP4 to 6 pin power adapter to power the graphics card, will this blow the power supply?

The PSU should current limit & shut down before it blows up.

The GFX card should have a minimum PSU spec on it, check that & let us know what the PSU is & the card manufacturrers recommendations.

Yes, I have installed the card but without connecting the power and the PC starts to boot up and then shuts itself down. Thanks for the prompt answer.

the cards usually come with a power adapter but if the PC is a new quad core, I'm surprised the PSU hasn't got one.

Should be OK, unless it's a mentally hungry graphics card, I ran my old one that way for ages and it was more like a heater than a graphics card 🙂

Really surprised the PSU doesn't have a 6-pin, on a modern PC…