That connector (6 pin PCI-E) is used to provide extra power for the graphics card, it does not plug into the motherboard but into a connector built into the card.
Are you SURE the powersupply does not have that type of 6 pin connector? Some have a 6+2 or even an 8-pin connector.
Take a look here, the PCI-E connectors are at the bottom of the first block of photographs.
As far s I know all current cards have these converters supplied with them as part of the package.
Normally it's not a good idea to use them but the 7770 will only draw a small amout of extra power so it'll be fine.
But, I am a little concerned: If the powewrsupply is so old it lacks a PCI-E connector it may not be suitable for your needs. Please supply us with the exact make and model of powersupply you have so we can be certain.
@robjordy: Surprised you recognised it Can't help but feel the poor hurricane does not get the recognition it, and its pilots, deserve-Just my little bit of respect for them.
I checkd my psu and i don't have both type of pins.........
I think have to buy new one.....
can you suggest me any motherboard having pciE 3.0 slot and supporting intel E2180 processor and a good psu having value for money
@ jaysingkar: There is no motherboard that uses the LGA 775 socket (for the CPU) and has a PCI-E 3.0 slot for the graphics card that I know of.
I would suggest you use the HD7750 instead, it's less powerful than the HD7770 but it does not need an extra power lead.