4890 Voltages and cooling.

[ObSo-1337]

I have been fiddeling around my with my graphics card voltages with GPU tool. right now, my VDDC voltage is at 1.5 (and im not too sure if that is safe or not). I have another voltage named "???" and its set to 1.2, can anyone explain what this voltage is for and could i increase it to boost my overclock?

Another thing. My 4980 is a hot one. right now, the RAM reaches around 90 degrees with the clocks at 1100 and i need some good heat syncs that will be suitable for dramatically reducing these temperatures. Any recommendations? The GPU also ventures into that 90 degree region, and im wondering if i should swap the coolers for my old Thermaltake DuOrb. Would this cooler be more efficent than the noisy stock cooler that came with my graphics card?

Oh and i dont want to increase the fan speed over 40% because it is seriously loud and annoying.

Thanks guys

 

[nafets]

1.5v is high for air cooling on a HD4890. ~1.4v is a bit more useable for 24/7 use.

The ???? voltage has some connection to the memory voltage. Increasing it does increase the ???? current, which I do know is linked with the memory clock speed. It is possible to increase it (using Rivatuner command-lines or GPUTool), but I am unsure of how much better the memory OC would be. Any actual gains above where you're at now would be minimal at best.

There is no actual memory chip sensor, so the temperature you're seeing (MEMIO) is just a subsection of the RV790 core.

Do not waste your time with other aftermarket coolers for your card. Especially the DuOrb. It would be highly ineffective at cooling your OC'ed HD4890. The VRM area of the reference HD4890 in particular is the hard part to keep properly cool with aftermarket air cooling.

Simply put, you need to increase the fan speed if you want to attain lower temperatures with your OC. Either that or lower your GPU/MEM clocks and voltage.

The stock reference cooler does a good job (with some noise of course) with a properly set fan speed.

 

[erocker]

1.5 volts is too much. Back your memory down too, the bandwith gained from going from say 1050mhz to 1100mhz isn't really worth the risk of frying the memory.

 

[ObSo-1337]

Thanks mate.
the reason for the high voltage is that i want to get to 1ghz stable, but i can only get to 980 with 1.5

yeah i assumed that was something to do with memory.

i already said im not increasing the fan speed. it is stupidly loud, i can hear the fan from downstairs, and my computer is up stairs. Is 90 degrees safe for this card? im not comfortable with my gpu being at that temperature though.

 

[nafets]

What are your VRM temps? If the GPU core is at 90C, I'd venture to say your VRM temps are even higher.

If the card is stable, then 90C is fine, but not great. You're just asking for trouble, in the long run.

Since you're sticking with such a moderate fan speed, something will have to give; IE...... your OC speeds and voltage.

 

[erocker]

Thanks mate.
the reason for the high voltage is that i want to get to 1ghz stable, but i can only get to 980 with 1.5

yeah i assumed that was something to do with memory.

i already said im not increasing the fan speed. it is stupidly loud, i can hear the fan from downstairs, and my computer is up stairs. Is 90 degrees safe for this card? im not comfortable with my gpu being at that temperature though.

Your GPU just isn't good enough to hit those speeds unfortunately. 90c is at the cusp of not being safe and I rekon that your voltage regulators are probablly at an unsafe temperature.

 

[ObSo-1337]

thats quite gutting. il turn down the voltage to 1.4 or 1.45 and see what overclock and temps i can get.

 

[ObSo-1337]

at 1.4 volts, fan is at 40% 930/1130 and im getting temps around 70 underload.

 

[erocker]

That's more resonable. Yeah, unfortunately we don't always get the pick of the litter when it comes to GPU's. I have a 4870 that didn't want to go over 780mhz. 70c under load with a utility is good since most, if not all games won't take it nearly as far.

*I remember taking that picture in your avatar btw.

 

[ObSo-1337]

haha awesome ;D

couldnt think of anything for my avatar
just went for that case because i quite liked it