S3500t Slimline 180W PSU with Radeon HD 5450 card

I got a hp s3500t with vista home 64bit OS, E7200 CPU, 4gb ram and now a new ASUS HD 5450 card bought to replace the Nvidia 9500gs that got to be too noise. But, although I did lots of research and thought I found the card with the lowest consuption on the market - something like 20 watts under normal load, my 180W PSU is probably preventing it from working. Specifically, now that I got the card installed I cannot open ANY video or flash material, I get media player, gom etc, crashes as well as flash crashes in youtube. But the PC itself does not crash and runs at normal resolution. Would you have any suggestion? Do you think it is the PSU? Should I get a 250 or 300 watts supply for this unlucky machine? Appreciate any comments.

re?>I was poking about and discovered this

In Device Manager
Under Display Adapter
ATI Radeon HD 5450
Conflicting device list:

Input/Output Range 03B0 - 03BB used by:
\Driver\VgaSave
Input/Output Range 03C0 - 03DF used by:
\Driver\VgaSave
Memory Range 00000000000A0000 - 00000000000BFFFF used by:
\Driver\VgaSave

Network Adapters 6TO4 Adapter X 10
Isatap
MS 6TO4 Adapter #28
#44
MS ISATAP Adapter #6
MS ISATAP Adapter #6


Could this be where the secret to my *crashing avi’s and flash* lies? Before I go an’ spend 60 bucks getting a new PSU shipped to Chile. Would you happen to know of any way to resolve something like this? Thanks very much in advance.


I have also updated to the latest Catalyst driver and still no effect, still anything remotely "visual" crashes, even Skype, but the pc itself works fine, word, explorer etc.