Laptop owners, beware of Windows 2000 battery management.

[Eug]

I had a problem playing DVDs, ONLY in battery mode. I tried multiple DVD players, but the result was the same. It was NOT due to Intel's Speedstep feature. While my PIII 600 MHz did slightly better than 500 MHz mode, it still could not consistently play DVDs, which is odd since I have an ATI Rage 128 GPU with heavy duty DVD assist built in.

Then further testing - I knew I liked Quake 3...

Quake 3 - 640x480, 16-bit, textures on low:

600 MHz, AC adapter: 49.7 fps (Hey, not bad for a laptop. )
500 MHz, AC adapter: 48.9 fps
DVD smooth as butttaaaaa!

600 MHz, battery: 31 fps (Ack! :Q)
500 MHz, battery: 28 fps
DVD jerky and sometimes locks up.

The weird part was that if the battery was fully charged, battery mode would give me results similar to the AC adapter mode.

Well, it turns out that the Windows 2000 laptop battery management mode really kills performance. However, the setup gives no indication that it would do that. But, now I have this machine set up as a desktop, all the problems have gone away. Strangely enough, the Windows battery management mode gives absolutely no indication that it does this. :| It just gives you options for monitor off, standby, hibernate, etc. Nothing about CPU speed.

Now the setup is purring along nicely. Got 256 MB in this baby as of today too.

 

[jeans2nd]

Does it matter what kind of laptop? Or is it all laptops just using Windows 2000? I know that IBM 76x laptops had problems with Lotus Notes dial-in while on battery, that's why I'm asking. Thanks!

 

[jaywallen]

Interesting. I wonder if this behavior is particular to specific equipment or drivers. I use an IDE 6X DVD on a Dell Inspiron 7500 (PIII 500 MHz, 128 MB, 12 GB) without seeing any issues with playback when on battery power. I don't do FPS, though, so can't say for sure how it behaves playing that type of game. In addition to movies, games like Riven and Crystal Key play just as well as they do on a desktop. And this system is not set up as a desktop. Perhaps on battery power Speedstep does something more than just throttling back the CPU? (I haven't had my hands on a Speedstep machine yet.)

Regards,
Jim

 

[Eug]

Well here are my specs:

Sceptre 69002 (aka Dell Inspiron 5000e or Compal N38W2)
Windows 2000 SP1
PIII 500/600 on a BX motherboard (100 FSB)
256 MB PC-100 SDRAM (most tests done with 128 MB however)
15" XGA TFT screen
ATI Rage 128 Mobility with 16 MB RAM
6 GB hard drive (Toshiba MK6014MAP)
8X DVD (Toshiba SD-C2402 with 1015 region free hacked firmware)
Built-in Lucent Winmodem
Linksys HomePNA & 10/100 Ethernet PCMCIA NIC

 

[Xanathar]

And what is your power settings in BIOS?

And how are you forcing the CPU to 600mhz and or 500mhz?

 

[lupohki]

For what it's worth, I have a Dell 5000e P3 500/600, 8MB rage 128, 196mb, winME and DVD playback while on battery mode is fine.

Xanathar,

New intel mobile processors have what's called Speedstep that allows you to lower to a specific speed to save battery life.

 

[Eug]

Yeah, I was forcing the speeds for the CPU by adjusting the BIOS settings. However, I just downloaded from Dell an Intel SpeedStep utility that does the same thing via software so I don't need to reboot each time. (Xanathar, this only works with laptop PIII/Celemine processors.)

I wonder if the battery management options between Win ME and Win 2000 are very different. Win 2000 is supposed to be a major change vs Windows 98 but I don't know what are used for Win ME.

I figured it was probably a problem with my OS when the Dell Inspiron 5000e users with WinME all told me they had no problems. Initially I thought it might be a battery problem since the Dell version uses a slightly bigger battery (59 Watthr vs 52 for mine). But I ruled that out when I started running programs like Quake 3 demo001, which didn't touch the ROM drive at all, and just barely accessed the hard drive.

Strangely enough, the defaults for desktop mode in the battery management are very stringent. If unused for a very short period of time then the monitor shuts down, then the drive, then it goes into standby, etc. In other modes it's much more lax by default, but I guess they compensate by this other method which is screwing up my performance. Or maybe it's just a bug but I don't think so.