MSI R7770-PMD1GD5 (HD 7770) Memory clock capped at 1300MHz???

[Darkmonk]

Hi guys,
Just started playing with my GPU tonight, on my new computer. Not new at computers or Tom's, but new at overclocking. I'm using this guide : http://www.tomshardware.com/forum/340404-33-wolfram-overclocking-guide

My problem(s) might be simple, but I can't find an answer(s!) anywhere, so I hope that someone can help me here ;-)

I use Afterburner. Ok, I know, can't modify core voltage with this card, and honestly I don't want to because I'm new at this and I don't want to break my card. I'm only moving that Memory clock cursor for now, doing some FurMark benchmarks. 4xAAS, 1920x1080, got a score of 2303 with an OC'd memory at 1300 MHz, stable for the 5 minutes suggested, score better from the previous 2251 points at 1275MHz.

1- Thing is, Afterburner doesn't let me go further than 1300 MHz. Tried Catalyst too, and can't. Any way to go further than 1300???

2 -Also, whenever I go past 1145MHz (core at 1065MHz instead of 1000), the "quick-accessed" Kombustor test crashes (doesn't even start, in fact! I'm talking about the test that runs when you just click on the "K" button in Afterburner, don't even know the settings of this test). Is that relevant? Or shoul I use FurMark and test with games, and don't bother 'bout Kombustor?

3- And finally, what does "Power Limit %" means? amuffin said in a previous post "Power limit is basically a slider that adjusts how much power the card can draw. If you want the best overclocks, have the slider to the max. This will allow the card to draw as much power as it needs and allows your overclock to be more stable!". Is that true? Without damaging the card? Then why the heck isn't this always at full???

Finally, many questions, but fell free to answer only the first and last, I can figure the second myself, have fun playing with this, and get two hits with the same stone

Thanks everyone ;-)

My built:
Asus PH77-V
Intel i3-3220 3.3 GHz
Corsair Vengeance 8GB
MSI Radeon HD7770
Corsair CX Series CX430
Cooler Master K350 Mid Tower
ASUS VH236H 23 Widescreen LCD Monitor

 

[amuffin]

Memory overclocking is a waste.

Aim for high core/shader overclocks, memory OC can possibly damage your card and won't yield enough performance increase.

Power limit is possibly there to allow users to tweak with their power draw?

 

[Darkmonk]

Thanks amuffin
oh and another quick question: is it possible that there's only one temperature sensor (core) and none on the ram? because I couldn't get that temperature even with GPU-Z
Thanks again

 

[amuffin]

Yep! That's very common, especially on reference edition cards. The only ones that have them are the twin frozr, hawk, lightning etc.

 

[Darkmonk]

Best answer selected by Darkmonk.