Problems installing Geoforce GTX 750 Ti

[njoeblair]

Hi there, I've got a HP Pavilion 500-366na with Intel Core i5, 6GB RAM, 2TB.
It's got the Intel HD 4600 Graphics Card which it came with.
It's struggling on quite a few games where I'm getting dropping frame rate issues. So following advice from the forum, I bought a Geoforce GTX 750 Ti and installed it into my HP Pavilion 500-366na.
This seemed to go ok.
I didn't think I needed to use the external PSU connectors as the advice I had was that I wouldn't need them.
However, If I'm honest, I couldn't see where I could connect them to (the 6 pin connector went into the card ok but I couldn't see anywhere on the motherboard or elsewhere to connect).
Anyway, I powered up and got the message 'please power down and connect the pcie power cables'
So, having searched around I have a few questions;
Is my problem that my power supply is insufficient? (Total wattage: 180 W external power adapter (100V-240V))
if it is, what do I need to replace it with? recommendations really appreciated.
OR
Do I need to connect the 2 pcie cables that come off of my 6 pin connector to something, if so what?|
any help really appreciated, I don't mind buying a new power supply if that is going to solve my problem.
Currently I have uninstalled my new card and everything is working ok, at present I have an integrated graphics card, so I haven't uninstalled anything or changed anything on my BIOS.
Thanks in advance for any help

 

[cin19]

Is my problem that my power supply is insufficient? Total wattage: 180 W external power adapter (100V-240V)

Open the case to check the PSU, I don't know what exactly mean "external 180W PSU". http://support.hp.com/us-en/product/HP-Pavilion-500-Desktop-PC-series/6879020/model/7265711/document/c04341334/ but if it is the 180W one, and the PSU can't power up the gtx750ti, you need 400W PSU or up.
If you are in USA, this one EVGA 500 B 80 PLUS BRONZE Certified 500W for $30 http://www.newegg.com/Product/Product.aspx?Item=N82E16817438012