XPS 15z: Screen brightness flicker/dim on battery by Intel "Display Power Saving Technology"

When on battery power, the brightness of the Dell XPS 15z LCD screen becomes unstable. If you switch from a bright web page (http://www.google.com) to a darker web page (http://www.nasa.gov), it automatically dim a little. It gets brighter the other way. It's almost like screen flickering when you switch between windows of different brightness.

Apparently this is a feature by Intel to  save power on battery. (Display Power Saving Technology)

"This feature extends battery life by lowering backlight intensity while minimizing impact to display quality. Select Maximum Quality for the best display quality or Maximum Battery to prolong battery life. Clear the check box to disable this option."

To fix it (if you find it annoying), go to Intel Graphics control panel and disable the feature.

Right click on some empty space on Desktop and from the menu choose Graphics Properties > Power > Change the pull down menu on power source from 'Plugged in' to 'On Battery' and uncheck "Display power saving technology". Click OK. Now the flickering should be gone.

I slid the bar to almost left (More towards 'Maximum quality' side) without disabling the feature and it also worked.

XPS 15z: Amazing battery life of 6-7 hrs for general use

I had been monitoring the Dell XPS 15z battery performance for last several days and I can now safely say that I get around 6-7 hours of battery for a normal use for me. By normal everyday use, I mean internet browsing with WiFi always on, chatting with friends, occasionally listening to music using an earbud headset, reading some e-books, writing some reports using Microsoft word, Windows explorer file copy/paste/move operations, browsing files/pictures on the hard disc, installing software here and then, downloading some files, remote connection to Linux work stations/supercomputers over SSH (secure shell) etc. Now if you just want to read an ebook or type in word and only occasional WiFi (disable/enable WiFi using Fn+F2 short key), you may get more than 8 hrs.

Here are some battery monitor logs collected by BatteryMon software from PassMark (http://www.passmark.com/products/batmon.htm)

In the beginning: 7 hrs of battery estimate

After 30 mins: Cloud streaming Google Music songs (http://music.google.com) with Firefox 4 browser for 10 mins drop down the overall battery life estimate to about 6 hrs. i.e, if you wanna stream music all the time, and browse normally you can use the laptop for 6 hrs max.

Returning to normal browsing and now the battery life estimate is back to more than 7hrs (7.5 hours of total estimated time).

 I used windows power saver option with lowest screen brightness(which is still good in a not-so-bright room). Since I do not use bluetooth,  I disabled all the bluetooth associated services.

Control Panel>All Control Panel Items>Administrative Tools>System services

There are four services with bluetooth name and right click on it. Go to properties and stop the service if t is running and change the startup type to 'Disabled'.Click ok. 

Also I disabled a few useless stuffs like Adobe updater, Adobe active file monitor, Dell Datasafe online bacup etc. (WARNING: Be careful in disabling stuffs like that. It may adversely affect your system performance. For example, if you disable Quickset using msconfig, it might result in a defunct DVD eject button.) One thing I must say is that I do not have any clear quantitative estimate of how much battery these services take up. May be some are harmless to battery life even if it is running in the background. Try yourself and find it out.

Now what will drain your battery for sure: 

1) The number one common thing could be playing flash videos while browsing; any news site  like CNN/MSNBC or youtube or all those annoying ads from 100s of sites. My recommendation is use Firefox browser with AdBlock and Flashblock if you happen to visit ad added sites.

2) Dell XPS 15z HD screen is exceptionally bright. I suspect full brightness use when not plugged in would negatively affect not only the battery meter reading but also the overall battery life. So make sure you decrease it. Also may be change default display colors to generic in Mobility center (Windows key + X)

There are many obvious stuffs which will drain your battery like playing video/DVD/running CPU intensive programs (games, video editing etc) etc. But I can assure you, this battery is simply awesome.

UPDATE: If you want to save a little more battery life, you may want to kill two cypress processes (CyCpIo.exe and CyHidWin.exe) through task manager (Ctrl+ Shift + Escape). However, you would lose minor touchpad functionality.

UPDATE: (2nd August 2011) I just found out a side-effect of disabling all the bluetooth services. If you go to Devices and Printers and you don't see any content but windows OS keeps on searching for ever, you have this problem. To fix it go to Control Panel>All Control Panel Items>Administrative Tools>System services and right click on Bluetooth Support Service > Properties  and make Start up type Manual. Then start the service. If you have that Devices and Printers windows open, your all devices will be shown instantly. wow!

_______________________________________________________________________
Some interesting Web pages

Browser Face-Off: Battery Life Explored
http://www.anandtech.com/show/2834

Top Tips to Extend Your Laptop Battery Life
http://www.pcmag.com/article2/0,2817,2324229,00.asp

Laptops with the best battery life
http://news.cnet.com/8301-17938_105-20007267-1.html

Dell XPS 15z Multitouch Gestures: User guide

UPDATE: An update for Dell XPS 15z users: Read it if you have some time
XPS 15z: Why you should not buy a premium Dell laptop
http://techienetizen.blogspot.com/2012/02/xps-15z-why-you-should-not-buy-premium.html

This multi-touch trackpad/touchpad feature is new to me and I had to spent some time to figure this out in Dell XPS 15z, fix the problems and get it working well.

Available options from the trackpad are:

a) 2-finger up/down or left/right: Scrolling (vertical and horizontal)

(PS: You have to have the window active and the cursor on top of it to use the feature; i. e if you try to do it for a background window, it won't work. Also if you have a scrollable window inside another scrollable window(eg. Gmail compose window), move the cursor appropriately like the old synaptic touchpad. If you want to scroll the background window, use a free program called WizMouse; http://download.cnet.com/WizMouse/3000-18487_4-10907935.html) It is quite useful for comparing two documents, web pages etc side-by side whicout having to click each window again and again)

b) 2-finger pinch zoom in and out. This was tricky for me. I didn't like it.

c) 3-finger up/down: Switch/change the tab of your browser if you have multiple tabs open, say in firefox. Unlike the above option of 2-finger scrolling, I had to lift my fingers slightly after each 3-finger up/down to get it work. I mean, if I keep fingers in the trackpad and do up then down, it won't go switch between the tabs.

d) 3-finger left/right: Browser/Windows Explorer go backward or forward. Again lift fingers after each left/right.

e) 4-finger up: It's like Alt+Tab, but the window selection panel stays without disappearing so that you can tap (or move cursor) on the trackpad to  select the window you want to change to.

f) 4-finger down: Shows desktop; similar to Windows key+ D

g) 4-finger left/right: Like Windows+Tab key combo. Open 3D window cycle panel with the perspective look. To cycle the windows forward, tap/swipe one(or more) finger keeping the other fingers on trackpad. (If you lift the fingers, the panel disappear zooming up the active window.) Each tap cycles to new window. When your cycle reaches the desired window, lift the four fingers, the window come up and become active for your use. I can't figure out how to cycle backward though; I mean Windows+Shift+tab option.

Now the main problem I faced was this one. When I actually want to scroll with two fingers, sometime it zooms in and out. If you have same problem, may be you can try disabling the zoom options so that you accidently don't zoom when you actually intend to scroll.   If you ever need Zoom options, use keyboard shortcuts (Ctr+, Ctr-, Ctr0)

Control panel> Mouse> CypressTrackpad > Click to Change Cypress Trackpad Settings > 2-Finger Gesters

Uncheck Zoom In/out Rotate boxes

I did this fix and it's working perfect so far.

If you want to enable the old style single finger scrolling, you can do that too.

Hope this might be helpful to someone with the same problem. Please let me know if I'm missing something so that I can learn from you.

UPDATE (June 20th): I was going crazy before I figured this work around but now I'm starting to like this option. There is a small learning curve to master this gestures, but once you get used to it, it'll become very convenient for your everyday browsing (if you use touchpad a lot; not using mouse). May be you need practice for 5-10 minutes. I would suggest you to give it a try.

UPDATE (July 4th):  I updated to the new Cypress trackpad drivers (v 2.3.6.5) and my experience went from awesome to awful. It gave me a frustrating 5-10 minutes of scrolling with jerky movements all the time. So I immediately restored to the old system state with System Restore. May be I'm missing something. I'm not sure whether the trackpad adapts and stores the usage behavior to give better performance? The driver version which I find working well is  2.3.6.3.

UPDATE (Dec 5th 2011):  I accidentally happen to see Dell Reps response to my Dell XPS 15z review on Dell.com. The update is that there is a new driver available for Cypress Trackpad. I copy paste the response here if anyone want to try it out. I'm currently test driving the new drivers and so far it looks interesting. I'll post my feedback on Dell forum soon.

Response from Dell.com:By Bill Bivin, End User Computing Solutions, December 1, 2011

Thank you for the excellent and well considered review. We very much appreciate the feedback. I wanted to provide an update specific to the touch pad drivers. The latest driver reduces the CPU load to peaks of roughly 2% each and a maximum combined average over a 30 minute sample of 1.9% in a normal usage scenario. Please try out the new drivers and post on the Dell Forums if you have any feed back. http://www.dell.com/support/drivers/us/en/usgen1/DriverDetails/DriverFileFormats?DriverId=1GFT0

http://reviews.dell.com/2341_ng/xps-15z/dell-xps-15z-reviews/reviews.htm?reviewID=15509786

XPS 15z i7-2620M Benchmark Performance

Windows Experience Index for Dell XPS 15z i7 model:

  Some performance testing and benchmarking results are here for Dell XPS 15z done with PassMark PerformanceTest ™  software (http://www.passmark.com/products/pt.htm) . Click on the image for the enlarged picture.

CPU mark comparison with other laptops

As per the test, the second generation i7 Dual core is clearly better than previous generation Quad core i7. Newer generation Quad core laptops are 75% better than new dual core i7.

Overall Passmark comparison with other laptops 

Looking at the overall "PassMark Rating" result for the laptop, Dell XPS 15z i7-2620M compares well with Alienware, HP Envy, Sony VAIO laptops.

XPS 15z: First impression

First impression highlights of XPS 15z from a user point of view: (After first two days of use)

Impressive:
1) The first thing I noticed and thoroughly enjoyed was the quality of the full HD (1080p) WLED 300-nit screen. It is a delight to watch full HD videos in actual resolution. It is noticeably bright and has a rich color reproduction when I played Sony and Philips 1080p HD video demo clips.

2) Of course, the images of the laptop are all around the web; it is slim, sleek metallic and stylish. No plasticy feeling.

3) The built-in dual mic audio recording quality is exceptional. Clear crisp voice from the mic near the webcam. It captured even my whispers in Skype audio test clearly.
UPDATE: I found out that Dell XPS 15z mics comes with enhanced noise reduction technology (Andrea Microphone technology); the reason behind such high quality audio recording.

4) The webcam is also impressive. Even in low light, the performance was quite agreeable. The associated webcam software (Dell webcam central) was particularly interesting paired with Skype video call.

5) The back-lit keyboard is pretty good in sensing the ambient light and kick in the back-lit in dark surroundings. Useful upgrade from my older laptop.

6) Not much bloatwares pre-installed! 5 years back, I got a Dell Inspiron installed with all the crapware which slowed down the already crippled Windows Vista. This time, even Dell software asked for permission to install in this laptop.

Just Ok, but not so good (nit-picking)
1) No dedicated 'Home' button. Okay, one will get used to it.

2) No USB port on right side. It would have been convenient to have one at the right.

3) An easily accessible play/pause/mute button in the front would have been very convenient

UPDATE: (July 4th) 
I found that there is an option to make dedicated media buttons in XPS 15z. Control panel > Windows Mobility Center (or use Windows Key + X). Then change the 'Function Key Row' option drop down menu and change it to Multimedia key.

I disliked:
1) Speakers are terrible. I can hear shrill sound in moderately pitched audio. Even windows logon audio is shrilled. My old Dell Inspiron speakers were much better.I heard XPS 15 has excellent JBL speakers. (But the audio output is superb, even with average headphone. No static hissing.)
UPDATE: I adjusted the volume and WavesMax audio setting at the Dell Realtek control panel. Now the sound is very clear and crisp without shrill. Yes, still it lacks appreciable base, but I do not expect quality base from speakers with such small form factor.

2) The strip of shiny rim surrounding the laptop is flimsy. I think it might come off sooner than later. I called Dell to check whether such potential cosmetic problem in future is covered in Accidental damage warranty and the answer was yes.

Wish-List:
1) Blu-ray drive: I already raved about the high quality screen. But unfortunately this laptop cannot fully utilize the full HD potential since it can't play blue-ray discs.

2) Why the 3.5mm audio jack cannot accept the headphone/mic hybrid input? Apple users can use their iPhone headset on their MacBook ulilizing mic for video chatting/conference. How about Dell smartphone users? They can't use their cellphone headset with Dell laptops. May be Dell will implement that in next generation 15z's. My current option is a mic/speaker splitter adapter (Smartphone Headset to PC Adapter) for about $15. Something like
http://www.amazon.com/gp/product/B00332DPDG


3) Option for a 128 GB SSD (since it might be cheaper than the current $560 upgrade cost)

4) Option for Windows 7 Professional/Ultimate

5) I hear that even better screen is there with XPS 15; Full HD B+RG LED screen would be nice to have in XPS 15z

Dell - Help Me Choose: LCD Displays
http://www.dell.com/us/p/d/help-me-choose/hmc-lcd-display-hd.aspx
"WLED Versus B+RG LED: White LED (WLED) is the standard for most screens. It means that a white-colored light diode is providing the illumination for your screen. Blue, red and green LED (B+RG LED), on the other hand, means that there are three light diodes — one red, one blue and one green — providing the lighting for your screen. This provides a richer color experience."

Still to test: nVidia, Intel HD Graphics card benchmarking, Battery life, heating/fan performance on moderate to above average use (to test any issue of overheating on usual usage).

List contents of a folder in Windows PC as text file

Sometimes you want to list and document all the files in a directory to a text file; for example, hundreds of mp3 files, thousands of pdf e-books or android apps apk cluttered in a folder. It is helpful if we need to keep an electronic record or to print and save the document as hard copy.

Linux does it with ls command in bash terminal.

'ls > directory_content_list.txt' will give the content of the directory in a text file 'directory_content_list.txt'

Now I wanted to list a directory in Windows.  An impressive software which would do this and much more is Karen's Directory Printer

http://www.karenware.com/powertools/ptdirprn.asp

  

If you don't want to install any program, there is one way to do it with DOS commands, but just by a few mouse clicks. The method is explained here very well.

http://www.forwestmedia.com/resources/how-to-guides/text-file-of-a-directory

Simply put, create a text file using notepad with the content below, save it as 'run.bat' file and run (double click) it. A DOS command window will pop up and the files will be created on your desktop, then opened in notepad. Remember to replace 'USER_WINDOWS_LOGIN_NAME' with your windows login name.

dir /a /b /-p /o:gen >C:\Users\USER_WINDOWS_LOGIN_NAME\Desktop\directory_content_list.txt
start notepad C:\Users\USER_WINDOWS_LOGIN_NAME\Desktop\directory_content_list.txt

Add Language Translate Menu to your Blog/website

I recently saw many visitors of my blog uses translation service to read the posts. I looked up for a button or link which can be conveniently used on the blog page for easy 'single click' translation. Google provides a nice java script "Google's website translator" for adding to your blog/website. This would be convenient for users who prefer to read the web content in their own language other than English. Here's the link.

http://translate.google.com/translate_tools

The script will add a drop down menu as you see at the right hand top corner of this blog. If you are adding to blogger/blogspot blogs, there is a button for that in the link page. This script would  convert English to 60 languages listed below

Available languages are: Afrikaans, Albanian, Arabic, Armenian, Azerbaijani, Basque, Belarusian, Bulgarian, Catalan, Chinese (Simplified), Chinese (Traditional), Croatian, Czech, Danish, Dutch, English, Estonian, Filipino, Finnish, French, Galician, Georgian, German, Greek, Haitian Creole, Hebrew, Hindi, Hungarian, Icelandic, Indonesian, Irish, Italian, Japanese, Korean, Latin, Latvian, Lithuanian, Macedonian, Malay, Maltese, Norwegian, Persian, Polish, Portuguese, Romanian, Russian, Serbian, Slovak, Slovenian, Spanish, Swahili, Swedish, Thai, Turkish, Ukrainian, Urdu, Vietnamese, Welsh, Yiddish

I wish it had an option to show menu language name title in it's native script/characters like here:

Language names in their own scripts

http://www.omniglot.com/language/names.htm

Connectify WiFi error: "UPnP not running"

How to fix "UPnP not running" error in Connectify?

I've already got Connectify hotspot setup and successfully running on my laptop. I also got my Android phone set up to connect to the hot spot. But sometime it fails to reconnect my Android phone (especially after waking up the laptop from sleep/hibernation). The WiFi connection in android WiFi setting shows as  "Obtaining IP Address" for a few seconds but unable to reconnect. The Connectify GUI shows the error "UPnP not running". This solved the problem for me: Just click through the 'Easy Setup Wizard" and finish it without changing anything (including password). Now the error should be gone and your device should be automatically connected (provided you have saved all the WiFi authentication credentials in your device)

Dual Layer (DL) read/writable? How to check if your DVD drive is capable of writing dual layer DVDs

If you want to write DVDs of size larger than 4.4 GB, dual layer DVD might be useful. How to check whether your DVD drive has the capability to write DL?  The free software DVD decryptor can do it.

http://www.dvddecrypter.org.uk

From the 'Tools' menu  > Drive > Capabilities

This shows that the drive can read both DVD+R, DVD-R DL but write only DVD+R DL

XPS15z vs XPS15 vs MacBook Pro

Dell XPS 15z vs XPS 15 vs MacBook vs MacBook pro 13 vs MacBook pro 15. I made this comparison table for my laptop purchase research and may be someone is looking for similar information. The information is as accurate to my information that as I can gather from Dell and Apple websites. Prices are as per the current time of the blog post. I also checked Sony VAIO Windows 7 options, but I do not have the spec-by-spec comparison. I remember that a system similar to XPS 15z was around $1800. Hope that helps.

Feature	Dell XPS 15z (L511Z)	MacBook Pro 15	MacBook Pro 13	MacBook	Dell XPS 15-L502X
Processor	2.70 GHz with Turbo Boost 2.0 up to 3.40 GHz  Intel Core™ i7 2nd generation processor  (Dual core)  4MB shared L3 cache)	2.30 GHz  with Turbo Boost speeds up to 3.40 GHz?  Intel Core™ i7 2nd generation processor (Quad-core) 8MB shared L3 cache	2.7GHz Dual-core Intel Core i7 4MB shared L3 cache	2.4GHz Intel Core 2 Duo	2nd generation Intel® Core™ i7-2620M processor 2.70 GHz with Turbo Boost 2.0 up to 3.40 GHz
HDD	750GB 7200 RPM SATA Hard Drive	500GB 7200 rpm SATA Drive	500GB Serial ATA Drive @ 5400 rpm	500GB Serial ATA Drive @ 5400 rpm	750GB 7200 RPM SATA Hard Drive
DVD Drive	8X Slot Load CD/DVD Burner (Dual Layer DVD+/-R Drive)	SuperDrive 8x (DVD±R DL/DVD±RW/CD-RW)	SuperDrive 8x (DVD±R DL/DVD±RW/CD-RW)	SuperDrive 8x (DVD±R DL/DVD±RW/CD-RW)	16x DVD+/-RW (standard), Blu-ray Disc™ combo (reads Blu-ray Disc™ & writes to CD/DVD); 12.7mm tray load
Memory (RAM)	8GB Shared Dual Channel DDR3 1333MHz Memory	8GB 1333MHz DDR3 SDRAM - 2x4GB	4GB 1333MHz DDR3 SDRAM - 2x2GB	4GB 1066MHz DDR3 SDRAM - 2x2GB	8GB 1333MHz Shared Dual Channel DDR3 Memory
Screen	15.6" 300-nit FHD (1080P) WLED Display	15-inch Hi-Res Glossy Widescreen Display (300-nit)	13.3-inch (diagonal) LED-backlit glossy widescreen display	13.3-inch (viewable) high-resolution, LED-backlit glossy widescreen	15.6 FHD B+RGLED TL (1920x1080) and Skype-Certified 2.0MP HD Webcam
Screen resolution	1920x1080	1680x1050	1280X800	1280x800	1920x1080
Graphics card	NVIDIA® GeForce® GT 525M 2GB graphics with Optimus. *	AMD Radeon HD 6750M with 1GB GDDR5	Intel HD Graphics 3000 (Integrated card; no dedicated card)	NVIDIA GeForce 320M graphics processor with 256MB of DDR3 SDRAM shared with main memory	NVIDIA® GeForce® GT 540M 2GB graphics with Optimus
Graphics card memory	2GB	1GB	384MB of DDR3 SDRAM shared with main memory	256MB of DDR3 SDRAM shared with main memory	2 GB
HDMI port	Built-in	Moshi Mini DP to HDMI adapter	Moshi Mini DP to HDMI adapter	Moshi Mini DP to HDMI adapter
Webcam	1.3 MP with dual mic	FaceTime HD camera. 1.3 MP	FaceTime HD camera. 1.3 MP	Built-in iSight camera	2.0MP HD webcam with single digital mic (H.264)
Keyboard	Backlit Keyboard - English	Backlit Keyboard (English) & User's Guide	Backlit Keyboard (English) & User's Guide	Backlit Keyboard (English) & User's Guide	Standard Keyboard - English
Card reader slot support	9-in-1 supporting SD, SDIO, SDXC, SDHC, MS, MS Pro, MMC, MSXC, xD	supports SD and SDHC cards	SD (Secure Digital) or SDXC (SD extended capacity) card slot	SD (Secure Digital) or SDXC (SD extended capacity) card slot	Support SD, SDIO, SDXC, SDHC, MS, MS Pro, MMC, MSXC, xD
Bluetooth	Bluetooth 3.0	Bluetooth 2.1	Bluetooth 2.1	Bluetooth 2.1	Bluetooth® 3.0
Touchpad	Multi-Touch trackpad	Multi-Touch trackpad	Multi-Touch trackpad	Multi-Touch trackpad	Multi-Touch trackpad
Mic	Two mics (dual array digital microphones;)	Single mic	Single mic	Single mic	Single mic
Ports	HDMI 1.4 (1),	Not available; external adapter needed	Not available; external adapter needed	Not available; external adapter needed	HDMI 1.4
	Mini DisplayPort (1),	Mini DisplayPort	Mini DisplayPort	Mini DisplayPort	Mini DisplayPort (1),
	RJ-45 (1), (Ethernet port)	Gigabit Ethernet port	Gigabit Ethernet port	Gigabit Ethernet port	Integrated network connector 10/100/1000 LAN (RJ45)
	headphone (1),	headphone (1),	headphone (1),	headphone (1),	Audio jacks: headphone (2 total) with SPID/F support (1), 1 Mic-in
	microphone (1)			Audio in/out
	USB 3.0 (2);	Thunderbolt port (up to 10 Gbps), FireWire 800 port (up to 800 Mbps)	Thunderbolt port (up to 10 Gbps)	MagSafe power port, Kensington lock slot	2 total USB 3.0
	USB 2.0/eSATA combo with PowerShare (1)	Two USB 2.0 ports (up to 480 Mbps)	Two USB 2.0 ports (up to 480 Mbps)	Two USB 2.0 ports (up to 480 Mbps	1 USB 2.0 (eSATA/powershare combo)
Wi-Fi	Intel Centrino Advanced-N 6230	Wi-Fi wireless networking4 (based on IEEE 802.11n specification); IEEE 802.11a/b/g compatible	Wi-Fi wireless networking4 (based on IEEE 802.11n specification); IEEE 802.11a/b/g compatible	AirPort Extreme 802.11n Wi-Fi wireless networking; IEEE 802.11a/b/g compatible	Intel® Centrino® Wireless-N 1000
	Not available?	Kensington lock slot
Battery	64 WHr 8-Cell Lithium Ion Battery	77.5 WHr Lithium-polymer battery	63.5-watt-hour lithium-polymer battery	63.5-watt-hour lithium-polymer battery	56 WHr 6-cell LI (2.6Ah) standard
Battery replacement	The battery is not user replaceable(?)	The battery is not user replaceable	The battery is not user replaceable	The battery is not user replaceable	Battery can be replaced by the user
Power adapter	90W	85W MagSafe Power Adapter with cable management system	60W MagSafe Power Adapter with cable management system	60W MagSafe Power Adapter with cable management system	90W AC adapter standard
Dimensions, weight	Height: 0.97” (24.68mm)	Height: 0.95 inch (2.41 cm)	Height: 0.95 inch (2.41 cm)	Height: 1.08 inch (2.74 cm)	Height: 1.3" (32.2mm) front /1.5" (38.2mm) back)
	Width: 15.15” (384.85mm)	Width: 14.35 inches (36.4 cm)	Width: 12.78 inches (32.5 cm)	Width: 13.00 inches (33.03 cm)	Width: 15" (381mm)
	Depth 10.25” (260.37mm)	Depth: 9.82 inches (24.9 cm)	Depth: 8.94  inches (22.7 cm)	Depth: 9.12  inches (23.17 cm)	Depth: 10.4" (265.4mm)
	Weight: 5.54 lbs (2.51 kg)	Weight: 5.6 pounds (2.54 kg)	Weight: 4.5  pounds (2.04 kg kg)	Weight: 4.7   pounds (2.13 kg)	Weight: Starting weight of 5.96lbs. (2.70kg) with 6-cell battery;
Case	Elemental Silver Aluminum	Aluminum uni-body	Aluminum uni-body	Polycarbonate unibody enclosure	Elemental Silver Aluminum
Warranty	2 Year Advanced Service Plan with Accedental damage protection. (Covers damages due to fall, liquid spill, broken screen etc)	Apple’s One-Year Limited Warranty	Apple’s One-Year Limited Warranty	Apple’s One-Year Limited Warranty	2 Year Advanced Service Plan with Accedental damage protection. (Covers damages due to fall, liquid spill, broken screen etc)
additional features	USB 3.0	Thunderbolt	Thunderbolt	Not available	USB 3.0
additional features	supports Intel Wireless Display 2.0, which means users can wirelessly stream HD content to HDTVs with an with an optional $99 adapter.	?	?	?	?
additional features	Waves MaxxAudio 3, Software’s ability to really give audio a boost. You can get 5.1 surround sound with external stereo speaker connection	Stereo speakers with subwoofer	Stereo speakers with subwoofer	Stereo speakers	JBL 2.1 Designed & Certified Speakers + Waves MaxxAudio® 3     2.1 Audio: 2 X 4W + 12W sub-woofer = 20W total peak audio performance
additional features	support for NVIDIA 3DTV Play which allows users to connect to compatible 3D TVs to display 3d photos, videos and games.	?	?	?	?
additional features					DataSafe 2.0 Online Backup 2GB for 1 year
Operating system	Windows® Home Premium, 64-Bit (No Prof/Ultimate options available)	Mac OS X Snow Leopard	Mac OS X Snow Leopard	Mac OS X Snow Leopard	Windows® Home Premium, 64-Bit (Prof/Ultimate options available)
Notable features	NO Blu-ray Option	NO Blu-ray Option	NO Blu-ray Option	NO Blu-ray Option	Blu-ray read and write
Price (excluding tax)	$1,499.99	$2,783.95	$1,499.99	$1,233.95	$1,334.99