PSU problems Need advice

[Naf456]

hi, guys (and girls)

2 months ago i bought an awesome ATI HD3850 (X turbo 3 version) graphics card from CEX (http://www.cex.co.uk/(which is like a 2nd hand store))
i've had problems with it on and off really. it works one day the the other it doesn't. now it doesn't work at all and my PC ,when i turn it on, does one long beep and 2 short beeps (where i've researched means a Video card error).

i took it back to CEX under the 12 month guarentee. theres this bloke there that had "supposively" tested my item
and he keeps telling me, even before he had look at the condition of the item, that it was all about my Power supply Wattage, that i need atleast 600 Watts to power it. but this is not what ATI recomends. they recommed 450 Watts!

in my Computer, i have:

550 watt PSU
An Amd 2.7Ghz black Edition processor
a 250 GB HDD (don't know the fequency)
a belkin Wifi desktop card
and a Disk drive

he told me that there was no hardware fault with the 3850 and that it's my PSU wattage. I came home and took out my Disk drive, Hard drive, Case LEDs and Wifi card and tried it again. still nothing happens appart from the SAME beeps. if the bloke was correct, the Graphics Card should boot and load my BIOS to tell me i have no HDD and disk drive plugged up to it.
Is this bloke Right and i need to get a 600 watt PSU, or is this bloke Corrupt and Doesn't want to take my Item Back?

any and all help appreciated

 

[hefox]

Could you give us more details about your PSU?

 

[uRSALOG]

unless youre running some ridiculous settings on your bios i dont see why youd have a problem with the card runing off a 550

 

[Onus]

Yes, what PSU do you have? A 3850 will run fine on 450W; heck an Antec Earthwatts 380W will have no trouble with it. If a GPU isn't getting enough power, typically it will shriek at you. The POST error beeps suggest the card is faulty. Did the guy test it again, in front of you?

 

[Mousemonkey]

CEX was always only good for selling your old broken/blown crap to, if it's in the original box they give you cash at least that's been my only experience with them and yes I have offloaded non-working cards, HDD's and RAM at one of their stores.

 

[Naf456]

Thanks Guys for all your Replys!

my PSU is a 550 watt

it's made By a Company call HEC?

it has 6 molex connectors,
one SATA power connectors,
a 24 pin motherboard connector,
a 4 pin motherboard connector,
and a 6 pin Graphics power connector.

this all i can really tell from it. the sticker on the side only says 550 watts and the company.
this is my fathers PSU really. my other one was 450 watts and the graphic card didn't work with it.

Thanks!