Is my psu local and bad

[anurag punk]

tomorrow i bought a cooler master 400w psu but it didn't came in a box , the seller told me that it doesn't come with a box but he handed me a warrranty card for 2 years on this psu , it has 17 amp on 12v rails and i had seen pictures of coller master 400w model on internet and it is the same that i have but how can i know that he didn't cheated me witha cheap 200w psu with a sticker of 400w of cooler master please help me .
my pc specs
intel core 2 duo e7500 @ 2.93 ghz
ram-2gb
hdd-320gb
gpu-sapphire radeon hd 6670 1gb ddr5
mobo- as3u3s3 p5kpl am in
and if its the real cm psu will it be sufficient for my pc .

 

[CM_USA]

Check the serial number of the psu to see if it's legit. See see below for "Warranty Check"

http://erma.coolermaster.com/member/

 

[Al1234]

To check if its sufficient for your needs, you check it on this: http://extreme.outervision.com/psucalculatorlite.jsp#footnote2