Extreme Newbie HELP (nTune overclocking on MBP)

OK, I have the 2.2 Ghz SR MBP with 128 vram running Vista 32 bit under Boot Camp with stock 1.4b drivers. This is my first time overclocking so I decided to play it safe and "overclock" just to Nvidia specs (475/700). I'm using nTune to change my GPU clock speeds.

I have a few really newbie questions:

1. Besides adjusting the core and memory clock speeds, is there anything else I have to do (e.g. adjusting voltage, etc.)? Also, I can't seem to adjust my GPU fan speed...is this normal?

2. How do I tell if I've gone too far in overclocking? What does the "stability test" in nTunes tell me? And what's a "good" GPU temp to aim for?

3. Will my system still automatically "downclock" in Vista & OS X if I'm not gaming or doing anything really graphically intensive? If not, is there any other way to get it to do so? Also, I just noticed that after I restart, the overclock settings are gone...is there any way to keep the settings permanent?

Thanks all for any help!

 

1. Dont touch the voltage unless you know what you are doing. Also you cant adjust it without modifying the bios of the card using something like NiBiTor and nvflash. Doing that sort of modifying probably isnt a good idea really. Core and RAM clocks should be fine unless your are trying to really push it to its limits which once again, probably isnt a good idea for a laptop GPU.

2. You know you've gone too far when you start seeing artifacts or snow. Artifacts are distorted shapes or lines and caused by too high of a memory overclock or the RAM is overheating. Snow are white dots that are caused by too high of a core overclock and usually ends with your system freezing or bsod. For max overclock you want to get it right when it starts artifacting (RAM) and snow or freeze (core). Then you drop it down maybe 5-10% or you overclock based on temperature. For a MBP i'm not all too certain what that temperature point is and im too chicken to overclock a laptop in the first place anyway.
The stability test tries to stress the card as well as other components in your computer some to see if any artifacts show up or if the system becomes unstable. Its an ok and simple way of seeing if everything will work basically.

3. I dont think theres an automatic way of setting a overclock after a restart with ntune. I know you can make profiles and what not but dont recall if it can load a profile at start.

Heres a thread about overclocking basics if you need more assistance
http://forums.extremeoverclocking.com/t89472.html

 

Wow, thanks for all the great info! That helps a lot...

Yah, I'm pretty chicken about overclocking my baby, too. I'm basically just bringing the clock speeds up to the specs that Nvidia lists on their site. So far, so good...

RE the stability test in nTunes, do I have to stare at the screen to look for artifacts/snow or will it tell me if there are any problems in the "Results" (mine says passed for all tests, whatever that means)?

Thanks again for all your help. The link's great, too.

Also, does anyone have definite answers to #3?

 

I wouldn't dare overclock a laptop graphics card anyway...

 

That's probably wise. As I said before, I'm really just bringing the clock speeds up to spec as Apple downclocked the card in the 15" MBP (their 17" is almost at spec using the same card so I *think* I'm in safe territory).

Anyway, I'm monitoring for artifacts, snow and temperature as I "overclock". Is there anything else I should be looking out for? For the temp, I'm getting ~82 C before the fans start going at it, bringing it down to ~75 C. Is this OK?

 

powz, I recently overclocked to 475/700. I've got the 256MB 8600m GT and used XP Pro so it would be interesting to compare results. It'd be better if we both had the same OS, but of well. Post your results in LightofHonor89's MBP Overclocking Benchmarks Thread if you have the time.

 

the gpu for the mbp is underclocked compared to nvidia's default clocks, the most i'd probably go is default. For a laptop card I'd overclock based on temps, according to istat and smc my mbp goes up to around 62C on load, the most i'd let it go up to would probably be 70.

 

Honestly it's best to play the games or run programs that use the GPU to it's extent and if you are happy then leave it alone. If you mess up anything Apple will not cover you under the warranty. Overclocking is really unnecessary and you will not be able to tell the difference after the nominal upgrade of the specs. Leave it alone my friend and spend more time enjoying that new Mac. Sounds like you are use to spending hours on end doing maintenance on Windows. The life of Mac OS X isn't about maintenance it's about using it and enjoying it.

 

Unfortunately I didn't do a baseline 3D Mark 06 benchmark, but after overclocking to the Nvida defaults I squeeked out about ~3300 marks. Not too bad but not exactly awe-inspiring. Seemed stable enough but then I tried playing Company of Heroes: Opposing Fronts beta on high settings. Comp froze twice from what I assume was overheating (couldn't read the stats after it froze but the underside was piping hot). Set it back to Apple defaults and hasn't frozen yet...and the game runs just fine.

Haha, you're 100% right. One of the reasons I got a Mac was to avoid all the hours of troubleshooting and tweaking. I think I'm slowly getting rehabilitated...it's a slow and painful process and sometimes I have relapses. Thanks for reminding me

 

I was under the impression that the MBP throttled the GPU and that it was not that underclocked? How far underclocked is it? Does it not step up when under a load? Also, my experience with overclocking has been minimal gains in performance, rarely worth the extra wear, especially in a notebook.

 

You're right on all accounts. The 15" 2.4GHz MBP is clocked at 470MHz Core and 635MHz Memory maximum. The idle/normal clock speeds are significantly lower. NVIDIA's specifications show a 475MHz Core and 700MHz Memory maximums for the 8600m GT. I found that the new 163.44 drivers at 470/635 yield slightly better 3DMark06 scores than the 101.34 drivers at 475/700 --> RESULTS. However, that was a really minor overclock. Others have reported larger performance increases with higher clock speeds on the 101.34 drivers. I don't really think it's worth it though.