Hardware acceleration | flash site gets slow sound is played before motion gfx

hey there

i have a as3 flash site

it runs great at my win pc (core 2 duo 4mb ram 1gb viga )

but when tested on Pentium 4 win pc it gets slower

i have a streaming video and audio in the site

at all the site became slower and especially the video doesn’t look smooth

what is the reason for that

i noticed there is a hardware acceleration option in publish settings is it the reason ?

or what is wrong on my flash site which works great on my core 2 duo pc

i have a flashing animation with gun shots sound it works fine on the core 2 duo

but

in Pentium 4 the gun shoots sound is heard before the flashing animation