GPU overclocking: core vs memory OC?

[Devrij]

Inspired by this thread http://forums.overclockers.co.uk/showthread.php?t=18439588

I'm now curious as to the benefits of overclocking memory vs core. I understand core overclocking and how it allows the gpu to do all the work faster (shading, polygons etc). I can see the benefits of it in fps increases.

But what effect does memory overclocking have? I'm guessing that it helps feed the data to the gpu faster so there are less delays and stuttering, but if you aren't experiencing a memory speed bottleneck (how would you diagnose this?), is there any point in overclocking it (and increasing heat/power consumption)?

Does anyone have any solid info on what exactly the effects of overclocking each of the components are, how they work together, and the benefits of each?

 

[Devrij]

Overclocking the memory on the latest generation of cards has a tangible increase in minimum/average FPS.

But why? I mean, I've overclocked my video ram as far it'll go and I saw gains, but I'm trying to understand the relationship between them. Purely out of curiosity, but if it's useful info that's a bonus too.

 

[Devrij]

I got it, so in theory it really depends on the game as to whether you're memory is bottlenecking your gpu. Wide memory bandwidth cards shouldn't need too much of a memory overclock then compared to narrower bandwidth cards? And the further you overclock the gpu, the more it would benefit from faster memory speeds to feed it?

I think I get it now. Thanks all, I may do some testing to see what effect it has on my card (5850, currently at 950/1200 from 750/1000). I have a pretty hefty gpu clock on it so maybe more memory bandwidth would come in handy for games like BF3