graphic card hd770 not boothing up sometimes from cold start.

[AMAZON]

HI i run a radeon hd7770 on a 775 gigabyte with a quad q9550. The card runs great all games and seems stable while playing. I have the latest drivers from AMD but the problem i have and ive just noticed this when i upgraded my drivers a few weeks back , used driver cleaner to get old drivers off..if i turn the pc off for a few hours and then go to turn my pc on again the fan spins high with not signal to the monitor i hear a post from the mobo. I use a crosair cx750m power supply so plenty of juice.To correct this I just have to turn the power off for a few seconds then back on and card boots up ok and can use it with no problems. I had no problems on booth up with my gtx 275 card, so could this be a small compt.ie AMD on a intel board issue because its the latest card on a old mother board. The problem does not happen all the time only when the machine is off for a good few hours. did not happen before when i first installed card only when i updated my drivers. thanks for help.
ps i have card connected to monitor from hdmi in card to dvi in monitor maybe problem?

 

[Tradesman1]

what PSU do you have?

 

[AMAZON]

crosair x750m

 

[AMAZON]

just switch it on tonight to send this message pc was off for 12 hours , switched the power on in the wall , then about 5 seconds after switched on pc all ok powered up ok could this be driver issues , when the pc starts the fan speeds up then slows down which i think is correct , the odd time ..but not tonight pc boots fan speeds up but keeps at this speed , the card is ok becuase i get the full gpu and cpu load in far cry 3...