This problem's pretty compounded in itself, and I've seen no proper addressing it in past topics, separate or combined, so here goes:
The notebook's an Acer Aspire 5050-3759. Turion 64; ATI chipset; 1GB DDR2; Battery's a classical 6-cells Li-Ion. Only difference with the standard model is a 100GBs Hitachi HDD instead of a 80GBs WD. Comes with Vista Home Premium, and several Empowering Technology applications pre-installed.
ePower is one of those applications, taking charge of handling the energy settings.
Under Vista, it offers a battery life of (roughly): 50-60 minutes with maximum power usage settings, around 2 hours with a balanced usage setting, and close to 3 hours with a minimum usage setting.
Now, when I installed XP SP2 on this notebook (fully patched and fine-tuned to the best of my knowledge), and the XP version of all Empowering Technology applications, ePower went buggy.
First of all, the battery life goes from 50 minutes to about 80, tops. That's all the change I get, when adjusting from absolute minimum, to absolute maximum battery usage. This obviously doesn't make sense, as something so radical as 1/3 screen brightness and 1/3 CPU speed should cause a vastly larger difference with maximum usage.
Also, though I'm not 100% positive about this yet, I think I noticed the fan(s) working at top speed all the time, regardless of adjustments. That is, the air coming out of the vent would be hot and strong enough to evidence that.
Moreover, upon one or two reboots, ePower stops working. It loads up, but trying to open it to make any changes will result in nothing. If you click on it on the Empowering Technology taskbar on the upper-right corner of the screen, its icon will come out to the fore twice (one for rolling over, two for the clicking), and that's it. Uninstalling then reinstalling doesn't fix this. With this current install included, this has happened on two completely separate XP installs (althought, both installs having been made by me, I could be making the same mistakes twice).
If it needs to be said...Normal XP energy management doesn't provide any significant differences. I get around an hour of battery life with it. And of course, I cannot make any of the advanced adjustments ePower provides me with.
I wish all these were just the software making miscalculations, but they're not phantoms. The battery life ends up being just as short as the involved timers indicate.
Could this really imply that XP is significantly worse than Vista at handling notebook energy settings? I really don't have much experience with Vista itself, but I really don't wanna have any, either. What little I do have, is negative, and not a single person in the know (including extremely well-qualified people) has told me anything but bad stuff about it. In short, I don't want it, and I know I should be able to make full, efficient usage of this notebook with XP.
Furthermore, it seems to be a heavier OS, thus how could it be more economic battery-wise? Everything I know, indicates that XP should be doing sizeably better than Vista on this. I've installed XP on multiple notebooks, including very similar ones (like, other Aspire models), and this is the only one that has presented this issue so far.
Another detail that may be significant: I've read very vague comments in other websites, about how AMD CPU drivers may affect things such as this. I downloaded all drivers for the notebook, straight from acer.com (a few needed an extra upgrade that XP searched for online automatically, but nothing bigger than that), and there was only one AMD CPU XP driver available for the Aspire 5050 series. I didn't install it, 'cos it's apparently for the Athlon only. I mean, I'm not positive, but it does say "AMD Athlon" in large letters in the logos when you run it.
Could this be the cause of the energy defficiencies? 'cos I doubt it could really be causing the "ePower won't open up" bug.
So, what should I do? Help offered by Acer's tech support is severely limited, since they only support this notebook with its pre-installed OS.
Does anyone know of a more efficient power managent application? Maybe that's the final solution?
Any and all help will be greatly appreciated. Thanks for your time.