GPU clock speed decreases when i open 3dmark

[Random_tech]

for some reason when i open 3dmark, the clocks speeds drop a lot.
the gpu i am using is a radeon hd5770.
the stock speed's (normal gaming) is 850MHz(core clock) and 1195MHz(memory clock).
and when i open 3d mark it goes down to 389MHz(core) and 900MHz(memory)

 

[stavrosmast]

probobly its overheating

 

[Random_tech]

no, it is well under 50°c.

 

[stavrosmast]

run gpu z and see its sensors then put gpu z in backround run 3dmark and then post a screenshot of the gpu-z max sensor values

 

[turbopixel]

Maybe psu problem, not enough juice or faulty. What psu and cpu do you have? Is the card new or old, how old? Didn't this happen before?

 

[Random_tech]

basicaly while 3dmark is open, the clocks won't get above what i mentioned before 398MHz/900MHz

 

[stavrosmast]

do what i told you before and tell us your full specs

 

[Random_tech]

Maybe psu problem, not enough juice or faulty. What psu and cpu do you have? Is the card new or old, how old? Didn't this happen before?

the card runs at full speed when playing games, it just won't run full speed while 3dmark is open.
BTW, my psu is corsair vs550w
my cpu is the pentium g3258

 

[stavrosmast]

reinstall drivers and 3dmark

 

[Random_tech]

http://imgur.com/CjpcjiQ
is the picture

 

[Random_tech]

i reinstalled it (3dmark). and i get this:

Unexpected error running tests.
Workload Single init returned error message: DXGI call IDXGISwapChain::SetFullscreenState failed [-2005270494]:

The requested functionality is not supported by the device or the driver.

DXGI_ERROR_NOT_CURRENTLY_AVAILABLE

and the speed goes down to the speeds mentoined before

 

[stavrosmast]

Probobly incompatibility issue or OC

 

[Random_tech]

there is no overclock on the gpu or cpu(all stock speed)
thanks for help though