well, depends on your system (no idea what you have) but that power supply is weak so nothing that would recquire a power connection. possibly a 7750 at best.
thats not a standard psu, so you cant just drop in a new one, unless you contact dell for an upgraded unit (wich wont be cheap, even if they are able to help you).
what are the rest of your system specs?
maybe its worth an upgrade but hard to tell without knowing the system.