I was referring to Alienware (which is owned by dell) purchasing their OEM parts from the company Clevo. Sager also buys the exact same parts from Clevo and changes the name just as Alienware does.
http://en.wikipedia.org/wiki/Clevo
As far as warranty goes, you get free lifetime toll free tech support & a standard 1 year parts & labor. You can increase that to a 3 year parts and labor for a about $250.
To compare them fairly I have customized both an Alienware and Sager laptop with as close to the same configuration as possible.
Area-51® m5790
Windows® Vista Home Premium
Intel® Core™ 2 Duo Processor T7400 2.16GHz
256MB ATI Mobility™ Radeon® X1800
17" WideXGA+ 1440 x 900 LCD
2GB Dual Channel DDR2 SO-DIMM at 667MHz - 2 x 1024MB
100GB Serial ATA 1.5Gb/s 7,200 RPM w/ NCQ & 8MB Cache
8x Dual Layer CD-RW/DVD±RW w/ Nero Software
Alienware® Intel® 945PM + ICH7 Chipset
Intel® 7.1 High-Definition Audio
$2,256.00
[FONT=Verdana, Arial, Helvetica, sans-serif]
Sager NP5750 - V
[/FONT] Windows® Vista Home Premium
Intel® Core™ 2 Duo Processor T7400 2.16GHz
128MB ATI Mobility™ Radeon® X1600 w/ 512 Hypermemory
17" WSXGA+ 1680 x 1050 LCD
2GB Dual Channel DDR2 SO-DIMM at 667MHz - 2 x 1024MB
100GB Serial ATA 1.5Gb/s 7,200 RPM w/ NCQ & 8MB Cache
8X DVD±R/RW / 4X+Dual Layer / 5X DVD-RAM / CD-RW Super Multi Drive
Intel® 945PM + ICH7 Chipset
Intel® 7.1 High-Definition Audio
$2,029.00 ($1,977.58 cash discount) No Tax