Battery Life
In the past, our standard battery life test has been provided courtesy of MobileMark 2005. Since the laptop isn't available with Windows XP (and we didn't have the necessary SATA drivers to even attempt installing XP), we decided to look elsewhere to determine battery life. Generally speaking, we don't expect people to seriously tax their laptops when they are unplugged, so we tried to come up with a benchmark that would simulate moderate office application use. The other most common battery life test is simply DVD playback, so we looked at that using Star Wars Return of the Jedi as our test DVD. (Don't complain -- it's a 2.5 hour movie so we didn't have to loop it more than once!)
For the other battery test, we ended up settling on Internet Explorer and simulated web surfing. We created a script that would start Internet Explorer and load our three home pages, all of which contained quite a few Flash-based advertisements. The script would then sleep for 60 seconds, simulating "reading" the web pages, and then it exits Internet Explorer and repeats the process. Internet Explorer was set to delete all temp files on exit, so it still creates a bit of hard drive activity. Basically, this test corresponds to about the best case scenario you are likely to encounter, while the DVD test is a bit more taxing.
Since we don't have similar results for the other laptops, we'll just report the two scores for each test in a table. It's not too surprising that the double capacity battery pretty much doubles battery life.
HP also offers a high-capacity 6-cell battery that should improve performance without adding all of the extra bulk of the 12-cell battery, but we didn't receive that battery and we're not quite sure how much more power that battery holds relative to the standard 6-cell. As it stands, the laptop either offers a somewhat limited amount of battery life, or if you get the larger battery you can end up with a pretty good mobile experience. Ideally, we would like to see minimum two hours of battery life, and probably closer to 2.5 hours as that's enough to watch just about any full-length movie on a single charge. Considering the performance isn't particularly stellar, we were hoping that battery life would be better.
Power Consumption
Related to the battery life discussions we've just finished, we have power results. For power testing, we removed the battery from the laptops and measured system power draw at the wall outlet using a Kill-A-Watt device. All laptops were configured to run at maximum performance when plugged into AC power. We tested several different scenarios to try to isolate the power draw of the various components. First, we have the baseline measurement when the system is idle and sitting at the desktop. No applications are running for 10 minutes or more and the screensaver and hard drive sleep mode are disabled. As a CPU load test, we run two instances of Folding@Home at 100%. Finally, for maximum power load we leave the two folding instances running and start 3DMark05. In this way, we can see roughly how much power the GPU is using in 3D mode versus 2D mode.
Looking at the power requirements of the system, the somewhat disappointing battery life is at least partially explained. At idle, power requirements aren't bad at all, but when the CPU is under load the power of requirements are quite a bit higher. We also noticed that the CPU had a tendency to not kick into the lowest power states; we discovered this using CPU-Z and the processor almost always stayed in the 8x configuration at idle, only bouncing up to 10x when one of the cores was placed under load. Normally, at idle, we're used to seeing the CPU dropping to the minimum power state -- in this case 1.0 GHz. It could be that the slight load that CPU-Z put on the system was preventing this from happening, but it also seems that Windows Vista was impacting the situation. Compared to the ASUS A8Js, the larger screen, hard drive, and faster front side bus all seem to balance out and result in a system that consumes only a bit less power at idle and quite a bit more power at load.
In the past, our standard battery life test has been provided courtesy of MobileMark 2005. Since the laptop isn't available with Windows XP (and we didn't have the necessary SATA drivers to even attempt installing XP), we decided to look elsewhere to determine battery life. Generally speaking, we don't expect people to seriously tax their laptops when they are unplugged, so we tried to come up with a benchmark that would simulate moderate office application use. The other most common battery life test is simply DVD playback, so we looked at that using Star Wars Return of the Jedi as our test DVD. (Don't complain -- it's a 2.5 hour movie so we didn't have to loop it more than once!)
For the other battery test, we ended up settling on Internet Explorer and simulated web surfing. We created a script that would start Internet Explorer and load our three home pages, all of which contained quite a few Flash-based advertisements. The script would then sleep for 60 seconds, simulating "reading" the web pages, and then it exits Internet Explorer and repeats the process. Internet Explorer was set to delete all temp files on exit, so it still creates a bit of hard drive activity. Basically, this test corresponds to about the best case scenario you are likely to encounter, while the DVD test is a bit more taxing.
Since we don't have similar results for the other laptops, we'll just report the two scores for each test in a table. It's not too surprising that the double capacity battery pretty much doubles battery life.
| Batter Life (Minutes) | ||
| HP dv6500t 6-cell | HP dv6500t 12-cell | |
| Internet Explorer | 133 | 246 |
| DVD Playback | 105 | 205 |
HP also offers a high-capacity 6-cell battery that should improve performance without adding all of the extra bulk of the 12-cell battery, but we didn't receive that battery and we're not quite sure how much more power that battery holds relative to the standard 6-cell. As it stands, the laptop either offers a somewhat limited amount of battery life, or if you get the larger battery you can end up with a pretty good mobile experience. Ideally, we would like to see minimum two hours of battery life, and probably closer to 2.5 hours as that's enough to watch just about any full-length movie on a single charge. Considering the performance isn't particularly stellar, we were hoping that battery life would be better.
Power Consumption
Related to the battery life discussions we've just finished, we have power results. For power testing, we removed the battery from the laptops and measured system power draw at the wall outlet using a Kill-A-Watt device. All laptops were configured to run at maximum performance when plugged into AC power. We tested several different scenarios to try to isolate the power draw of the various components. First, we have the baseline measurement when the system is idle and sitting at the desktop. No applications are running for 10 minutes or more and the screensaver and hard drive sleep mode are disabled. As a CPU load test, we run two instances of Folding@Home at 100%. Finally, for maximum power load we leave the two folding instances running and start 3DMark05. In this way, we can see roughly how much power the GPU is using in 3D mode versus 2D mode.
| System Power Draw (Watts) | ||||
| ABS Mayhem Z5 | ASUS A8JS | ASUS G2P | HP dv6500t | |
| Idle | 44-49 | 26-32 | 43-52 | 22 |
| 100% CPU | 67-71 | 47-52 | 71-81 | 57 |
| Maximum | 100 | 71 | 97 | 67 |
Looking at the power requirements of the system, the somewhat disappointing battery life is at least partially explained. At idle, power requirements aren't bad at all, but when the CPU is under load the power of requirements are quite a bit higher. We also noticed that the CPU had a tendency to not kick into the lowest power states; we discovered this using CPU-Z and the processor almost always stayed in the 8x configuration at idle, only bouncing up to 10x when one of the cores was placed under load. Normally, at idle, we're used to seeing the CPU dropping to the minimum power state -- in this case 1.0 GHz. It could be that the slight load that CPU-Z put on the system was preventing this from happening, but it also seems that Windows Vista was impacting the situation. Compared to the ASUS A8Js, the larger screen, hard drive, and faster front side bus all seem to balance out and result in a system that consumes only a bit less power at idle and quite a bit more power at load.
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JarredWalton - Tuesday, June 26, 2007 - link
Funny you should mention the E-155-C.... :DFant - Friday, June 22, 2007 - link
Seems HP shipped you a badly specced machine. They should have used a 5400rpm drive and the nvidia graphics chip as well as the extended 6-cell. All three would have improved your benchmarks. Out of curiousity, did you use a clean vista build or the out of the box vista build that hp supplies with loads of extras installed?JarredWalton - Saturday, June 23, 2007 - link
HP's install, minus a bunch of software that I didn't want running. Although, when I ran SYSmark 2007, I ahd to do a clean install first. (Now you know why the lack of GbE was annoying - image a HDD over 100 Mbit and I averaged 3 MB/s instead of 12 MB/s with GbE. Not sure why, but Acronis only manages to use about 25% of the Ethernet bandwidth.) Anyway, I like to make the testing close to "real world", and most people don't buy an HP, Dell, Gateway, etc. notebook only to install their own operating system. (Businesses are different story, but let's not go there.)I actually don't think that the configuration they sent was all that bad. It may not perform as well in benchmarks, but the fact of the matter is that a lot of people get way too hung up on benchmark results. Do you want a faster hard drive, or do you prefer having a bit more storage? There is no right answer, although personally I would generally go with one of the 120-160GB 7200 RPM laptop drives if possible. As for the battery, they did send me the 12-cell for testing, and the only thing I really would like to know is the capacity of the extended 6-cell. The basic 6-cell is a 47 WHr, so if they extended capacity is 65 WHr it would increase battery life by about 35-40%. I'm trying to get an answer from HP about the capacity of the other 6-cell offering.
Fant - Saturday, June 23, 2007 - link
I have a dv6500t with the extended 6-cell. I havent done any formal testing but I probably get just under 3 hours with the HP Recommended / Balanced Power Plan in Vista and a bit over 3 hours when using the Power Saver Plan. I did notice that the cpu seems to stay at the lower speed with the Power Saver Plan but seems to stay at the higher speeds with the HP Recommended / Balanced Power Plan even when I am not doing much cpu intensive tasks.JarredWalton - Saturday, June 23, 2007 - link
Can you check the battery and see what the rating is? Usually it will say something like "10.8V ~= xx WHr". I want to know the Watt-Hour rating. I'm not sure why, but the notebook I have almost never runs at minimum CPU speed. Weird.hubajube - Friday, June 22, 2007 - link
I was waiting to read on how this laptop performed when watching HD DVD's. I'm interested in buying this for my wife for her to use as a work laptop but at the same time I'd like to use it as a HTPC. Oh well guess I'll have to spend the money to find out. :(JarredWalton - Friday, June 22, 2007 - link
Yeah, they didn't send the HD-DVD version. I'm not sure if the 8400M GS is required for that or not - maybe X3100 can do enough to handle it (but I doubt it). Anyway, we've tested 8600 cards with HD-DVD, and I don't see why the 8400M wouldn't handle it fine. Problem is, the display is still pretty poor, especially when you consider that video overlay can have a color correction profile applied.shady3005 - Friday, June 22, 2007 - link
I was gonna consider this laptop but was turned off by the lack of gigabit ethernet. Dint know about the horrible display at that time. So i was waiting for an upgrade to this laptop but sadly none came.Then I set my eyes on the new Macbook pro. Just 500$ higher that top dv6500t config but worth every extra penny. Amazing display , much lighter , thinner , sexier and CPU (2.2Ghz) and Graphics (8600GT M) upgrade with much better battery life.
Please review the new MacBooks with Santa Rosa ..... I would like to hear how awesome they are ..
crimson117 - Friday, June 22, 2007 - link
I lol'd pretty good at this one :)
BPB - Friday, June 22, 2007 - link
Maybe I missed it, if so please excuse me, but I think you simply used the ABG wireless setup. I was wondering how well the N wireless works, and how well it talks to other N devices such as my Belkin N1. My wife's HP works quite well with the Belkin N PCMCIA and router, but for our next notebook I'd like to have the N built-in.