Do i need to upgrade my powersupply?

[CHILAX747]

Here are my system specs

Power supply - Corsair 400w CX

Processor- Intel E8400

Motherboard - ASUS P5QL - EM

Primary hard drive - WDC 160gb

Secondary hard drive - Samsung 500gb

In PCI slot - Leadtek Winfast Dtv 100s

Ram - Kingston 2gb
Transcend 2gb

Graphics card - Nvidia 8400 gs 512mb

Heres probably something that's important - I have a Thermaltake V9 Black edition case. i have a 12 cm front fan , a 23cm side fan , a 23cm top fan , and a 12cm rear fan running off the power supply , too.
I decided about a month ago to start saving up for a better graphics card. Now i have about $180AUD to spend on a graphics card. I have found a good GTS 250 that i like , and i have also found a good OCed 9800gt.
Heres my question.
I have began to think that maybe a GTS 250 would be a bit much for my power supply. im not sure 400w is enough for a GTS 250. I have read EVERYWHERE that my Corsair 400w cx is very good quality, but im still not satisfied that 400w is enough for a GTS 250 with my system.

If the specifications for the Graphics cards i found are needed i would be happy to post them.

So
Is it recommended that i get a new power supply?

Cheers,

Chilax747

 

[illegalmonkey]

It may be good enough. Was reading reviews on Newegg.com and seems like it'd be able to do it. If not, worse that can happen is it just won't power on, then you'll know to get a new psu. a 520 will prob do you good.