The system needs an OEM adapter to charge the battery, so you're limited to what Dell supplies -- and the power requirements are not going to allow for a lower-capacity adapter.

Hi @Coolhandluke67 welcome to this free user-to-user Alienware laptop discussion forum. 

Part Number 0405B20220 is 220W ac adapter for Clevo and Alienware. There are slim 220W ac adapters DP/N 
G5K8G 240W Chicony slim (m15 R5/R6, x15 R1/R2, x17 R1/R2)
R4P0K 240W Delta slim (m15 R5/R6, x15 R1/R2, x17 R1/R2)
4GC66 240W Liteon slim (m15 R5/R6, x15 R1/R2, x17 R1/R2)

There is a slim 330W ac adapter for x17 R2. New Slim 330W GaN AC Adapter Charger For Ali X15 X17 R1 R2 GTX3080 HA3 (allacadapter.com).  

The New Thin Genuine Dell Alienware 330W GaN Charger X17 R2 19.5V 16.92A ac adapter is DP/N
5P90C 330W Delta slim (x17 R2) 
8K4F9 330W Chicony slim (x17 R2) 
C6PGW 330W Liteon slim (x17 R2) 

x17 R1, get x17 R2 330W SFF AC adapter (GAN charger)? - Dell Community  

Yes the 220W is correct, but all those chargers have something like 17A, where mine has 3A. So I don't think that would work right? Please correct me if I am wrong. I did notice that when I search for low Amp chargers they usually are big bricks...

Hi @Coolhandluke67 thank you for sharing question, please revisit your opening post for input & output. There is option of going to OEM Alienware M17 Parts & Upgrades to purchase Dell 7.4 mm barrel 240 W AC Adapter with 2meter Power Cord - United States. 

This is a different m17 alienware laptop. It is a bit confusing, why they have the same model nr for 2 different computers is beyond me. My laptop is from 2008, and weighs probably 3 times more then that m17 laptop which is more modern. I need a charger for my m17 laptop from 2008.

Hi @Coolhandluke67 agree it is confusing to have same model ID for 2 different computers. Please click on Product Support so that Dell can identify your 2008 Model and Revision number. Thank you. 

I do not see a Dell Alienware laptop that was released in 2008? I wonder if yours was one of the Legacy pre-Dell Alienware Laptops?

M17x R1 (6/02/2009)
M17x R2 (1/15/2010)
M17x R3 (1/08/2011)
M17x R4 (4/19/2012)
17 R1 (6/25/2013)
17 R2 (1/08/2015)
17 R3 (9/16/2015)
17 R4 (9/30/2016)
17 R5 (4/16/2018)
m17 R1 (1/06/2019)
m17 R2 (7/01/2019)
m17 R3 (5/21/2020)
m17 R4 (1/26/2021)
m17 R5 (4/18/2022)
x17 R1 (6/15/2021)
x17 R2 (1/27/2022)

Hi @Coolhandluke67 would it be possible to share picture of your 2008 laptop? 

Charger model 0405B20220 for Clevo & Alienware laptop has 4-Pin power cord. 

I wanted to do that when I posted, but I didn't see any option for uploading pictures. However I found someone else who is selling the same one I have. Below is the link.

https://www.goodwillfinds.com/electronics/computers-and-tablets/laptops/alienware-m17-r1-intel-core-2-quad-2.0ghz-memory-4gb-screen-17inch/10012-0000-108678.html?gclid=EAIaIQobChMIjauhutnL_QIVQP7jBx0P2A-YEAQYAiABEgKKbvD_BwE

My mistake, 2009 not 2008. It is the top one, M17x R1 from 2009