7950 overclocking query

[The Only Beardy]

Hey,

I am currently rocking a Sapphire HD 7950 OC at 1175/1500 1.175v and this seems relatively stable. I am air cooling and temps go up to around 90. After half an hour or so of gaming the screen flickers with weird strands of colour. I am gaming at 1440p.

I was just wondering if anyone had any recommendations of what I could do to make this more stable...

What should the limitations be for a 7950 gaming at 1440p be? will i be able to cope with BF4?

 

[se_vietboi]

That is definitely not a stable overclock and 90c is high (especially with a aftermarket cooler) so I suggest lowering the core clocks and voltages. Personally I'd put it at 1100 core and lower the voltage with small increments until stability is achieved.

A 7950 should be able to run BF4 smoothly -60FPS- at 1440p near high settings but to max everything you may consider crossfiring.

 

[UKDTweak]

I have a HIS IceQ boost with none boost bios, stock runs at 925/1250 at 1.175v but boosted to 1000/1250 at 1.250v, using afterburner I set voltage to 1.250v and run stable at 1200/1500, fan at 60% and temps not gone over 60 so far, so firstly I would increase your fan speed to cool it better and see if that helps otherwise either lower your clocks or try raising the voltage a little (as long as your temps stay well under 90!).

Plenty of guides on the site for best overclocking methods

 

[The Only Beardy]

Ah thanks guys,

I currently have the fan speed set to auto and it goes up to around 75% i believe. I'll try and lower clock speeds and see if I can reach a more stable overclock.

I have been considering crossfireing, but unfortunately I am lacking in funds right now.

Without overclocking though my 7950 sits around 71... is that still high?

 

[UKDTweak]

That sounds a little high, perhaps you need better cooling in your case, what setup do you currently have fan wise?

 

[The Only Beardy]

I have the stock coolers that come in a Corsair 600T White and my CPU cooler is a Noctua NH-D14 (I dont have any issues cooling my CPU).

When I use my GPU for gaming and such, i use the fan controller on the front of the case to ramp the fan speed up... this is all i have currently.

I was thinking of getting a couple of the 200mm Spectre Pro's, but again, my budget is pretty tight at the moment.

 

[UKDTweak]

Ok, just thought maybe airflow in your case might be bad as your 7950 temps seam a bit high, though you have a different make of card and so a different cooler to mine...

What sort of temp is your CPU getting when under load, is it high too?
Do you have a fan bringing in cold air from the front and a fan pushing out hot air at the back of the case?
Have you tried running with the case side off to see if it makes any difference to temps?

 

[The Only Beardy]

I don't know whether you know the case at all, but i have removed one of the HDD bays and moved the other one back so that it is right next to the PSU. This has given more flow from the fan in the front.

I believe my fan configuration is 2x200mm fans pulling in from top and front and a single 120mm fan blowing out the back.

My CPU doesnt really go above 65 on load. Thats running at 4.5Ghz....

I do notice a slight difference when i remove the dust filter from the front.

 

[UKDTweak]

Ok, then it sounds like your 7950 cooler is not well fitted perhaps, but i could be wrong, as I can only judge based on my HIS model, I would take off your 7950 OC for the time being and see how the temps fair, if you still get high temps AND artifacts at stock speeds I would RMA it.
My card will only do 1150 at 1.175v so you are probably getting artifacts due to undervolting and high temps, reduce the core speed and re test while monitoring temps.

 

[The Only Beardy]

Ah right,

Well I'm not at home at the moment, I think I'll remove the OC and leave it there for the time being. If i start to struggle with games, then I'll rethink the OC.

Hopefully by then I'll have the funds to buy a second 7950

Thanks!

 

[tommybhoy]

I believe my fan configuration is 2x200mm fans pulling in from top and front and a single 120mm fan blowing out the back.

Airflow, too much coming in, nowhere for the hot air to escape quickly enough.

Turn the top fan round to vent along with the 120 fan.

Get another fan to push air through the front if you can too.

Ideal temps for oc'd Tahiti is keeping it under 75c max.