Questions about GPU core clock, memory clock and voltage control

MikeyLinton1187

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Hello, I was wondering what exactly core clock and memory clock are for. I have done a bit of searching and think I have an idea of whats going on, but just wanna check.

1. Is the GPU memory clock essentially how much vram the card has or is it the number or timers per second the vram can be accessed per second, similar to system ram.)
2. What exactly does increasing the core clock do, I realise it increases performance, but does allow more instructions at a given time or more instructions per second or what?
3. This is specific to AMD WattMann: Are the 2 different voltage controls the voltage supplied to different parts of the card. i.e. If my highest voltages are 1030mV and 1000mV (for core clock and memory clock respectively), is the total voltage my GPU is drawing 2030mV?

Thanks,
Michael
 

Max1s

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Your graphics card has a GPU chip (graphics processing unit) that consists of a large number of cores. These cores do calculations and build the virtual in-game environment. However, it needs memory (or "VRAM") to do these calculations.

The GPU cores do very many operations per second, the rate at which they do these operations is the "clock" speed.

The GPU can run at a higher clock speed, but it will need a higher voltage, and it will use more power and give off more heat. This is where the fancy software comes into play, it keeps your card running as fast as possible while still staying within temperature/power limits.

Your card has different components on it (GPU, memory, etc) that need different voltages, the voltages don't stack in the way you've mentioned.
 

Max1s

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Your graphics card has a GPU chip (graphics processing unit) that consists of a large number of cores. These cores do calculations and build the virtual in-game environment. However, it needs memory (or "VRAM") to do these calculations.

The GPU cores do very many operations per second, the rate at which they do these operations is the "clock" speed.

The GPU can run at a higher clock speed, but it will need a higher voltage, and it will use more power and give off more heat. This is where the fancy software comes into play, it keeps your card running as fast as possible while still staying within temperature/power limits.

Your card has different components on it (GPU, memory, etc) that need different voltages, the voltages don't stack in the way you've mentioned.
 

MikeyLinton1187

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So essentially the GPU cores need memory to store data so it can fetch decode and execute, just like the CPU and system memory (ram)?

EDIT: But will decreaseing the voltage of one decrase the overall voltage drawed or is it a ratio and i need to bring both down to bring voltage draw down?
 

Max1s

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Yeah as far as I know, CPU's + RAM are very similar to GPU's + VRAM, it's just that a graphics card will have thousands of weak cores vs a CPU that will have a handful of powerful cores.

Don't think about "total voltage drawn," think about total power. Are you thinking about under-volting your card or is this just a theoretical question?
 

Max1s

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I think you should be able to do it in software. You'll want to use the lowest voltage where the card can still run stable. So set an ambitious under-voltage, then run a stress test. If the test fails, bump the voltage up a bit, and keep doing this until you can run a stress test for several hours without failure.

But that's from my experience overclocking CPUs, I would seek advice from someone with more experience with what you are doing. Just search for threads about under-volting the card. Even threads about overclocking the card will be useful to you, since you have the same goals (lowest voltage for highest clock rate) , but you're not changing the clock.

Which card do you have? I think under-volting was pretty popular with the AMD RX470 and RX480.
 

MikeyLinton1187

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Ok thanks for the help. I have an RX480 8GB
 

Max1s

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Right, just google around, I'm sure you'll find plenty of information. If you still have any questions after researching, just open another thread here, but name it more specifically, ie "RX480 undervolting"
 

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