PSU not able to give enough power?

[cmeyvin]

I bought a HD 4850 today. I ran it on a generic brand 500W PSU using 2x 4-pin to 6-pin connector. plugged everything in and booted the pc. everything worked fine. temps were good and I was able to play my games no problems for an hour. I didn't screw in the screws for my hdd yet so I shut down the pc so to put the screws back in. Now when I boot up the pc again, nothing appears on the screen. I get this beep code, one long and two short. I also notice that the CPU fan takes time to start running and same for gpu fan. or it boots up tries to get the cpu fan to turn and then reboots by itself and both the cpu and gpu fan turns but still nothing appears on screen. but if i put back old graphics card (9400gt) boots up just fine no problem at all. What is the problem here? Also, tried to remove the DVD drive and HDD and the problem was not resolved

sticker of PSU:

running the 4850:
https://www.youtube.com/watch?v=MoXbOfFUBtU

now running my old 9400gt
https://www.youtube.com/watch?v=haKuGlJoq-U

notice the CPU fan

 

[zir_blazer]

Radeons 4850 were a power hog if I recall correctly. Maybe you're asking a bit too much from the generic Power Supply, more so if it doesn't even has a native PCIe connector. Says thanks if it didn't blow up already, because they usually lack any kind of overpower protections.

 

[cmeyvin]

Radeons 4850 were a power hog if I recall correctly. Maybe you're asking a bit too much from the generic Power Supply, more so if it doesn't even has a native PCIe connector. Says thanks if it didn't blow up already, because they usually lack any kind of overpower protections.

so the card's still fine? I just need to buy a better power supply? I'm thinking of getting a corsair CX

 

[Freddy1765]

How come you bought such an old card? D: