Overclocking 4850

[Guest]

My friend has a dell optiplex 745. we added an ocz 850 watt power supply, and a hd4850 diamond to it. I have the newest drivers along with the hotfix. I auto tuned the card and speeds were set at 690mhz and 1033mhz. I start up Crysis the game, I load my campaign, I play about 2 mins in then it freezes, screen drops, an ATI box comes up saying something about not receiving video from the driver and then my screen goes black saying entering power save mode, then the game comes up for a min then freezes again doing the same as before, i can play crysis fine when i dont overclock it. Please help

 

[jitpublisher]

From my experience, the auto overclocking feature does not work well at all.
It is far better to do it manually, run it and test it.
Don't overclock the memory at first, the memory speed is quite sensitive.
Start out by just overclocking the core speed, and keep an eye on the temps. When you reach the max core speed you can run without problems, back it down slightly, like 20~25mhz, then SLOWLY start raising the memory speed. But do not be suprised if you can only go a little ways with the memory.

 

[Guest]

yeah i tested the overclocked speed and the temp never got over 69 degrees celcius, this is the part i dont get, the card isnt running hot but wont play a game with the new speeds. Aggravation a risen. lol

 

[jitpublisher]

Try it manually, your temps look fine.
It takes a while and some playing around, but you will get much better results. The problem I find with the auto tune is that it pushes the memory to far to fast. If you leave the memory at standard speed, you will find that you can go a long ways with the cores speed. The memory speed increase doesn't really help all that much anyway.

 

[Guest]

i will keep in mind what you have said about raising the speeds one at a time and core before memory, but any idea on why when i start playing a game that the ati box comes up and then my screen says entering power save mode, btw thx thus far

 

[jitpublisher]

Does it do this at stock speeds? That is usually the first indicator of a bad overclocking situation.
Are you running the lastest drivers from the AMD website?

 

[Guest]

At stock speeds no, i have the 8.11 drivers with the hotfix as well. i also used rivatuner instead of CCC with same results, also tested playing crysis at stock speed and temp never went above 57 degrees Celsius.