Photo Editing: why would a large frame buffer help?

Lo people,

I'm a little perplexed.

QX6700 with 4 gig ram
XP Pro 32bit
Intel mobo
Paint Shop Pro 8
24 " Hyundai tft (stunning it is, too)

Had an ATI HD 2600 card in. 256mb
Now has an ATI X1900 XT in. 512mb

Why would photo's open up notably faster in Paint Shop Pro with the larger frame buffer?

It's quite noticeable. As soon as the card was swapped, the photo's opened quicker. The only other thing that changed was going from a Dec '08 Cat driver to March '09 when the card was swapped.

Both cards run GDDR3, though the X1900 is faster ram, and on a 256bit bus.

But surely that can't make a difference in 2d photo's.

Gaming, bleedin' obvious. Desktop is same as before. Apps open same speed. Its the same CPU and RAm amd MOBO and HDD after all.

But photo's open quicker. I cant get my head around the maths. Not enough coffee I guess. These arew 10mp photo's but whether they are opened singularly or in multiple's... it's faster. Are photo's moved to the frame buffer any quicker if there is more of it?

Surely 256mb frame buffer was enough for one 10mp photo?

Suffice it to say, I lost my X1900 XTto my Dad and have returned with an HD2600 :-/ but he's happy so that's good.

Quote:

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Originally Posted by Zak33

Both cards run GDDR5

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That should read GDDR4 - just nitpicking!! The only way to be certain about the speed is to compare both cards with the same driver release.

Quote:

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Originally Posted by Zak33

though the X1900 is faster ram, and on a 256bit bus.

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Just a guess....

;)

It's unlikely to be frame buffer size as much as a faster GPU and higher memory bandwidth.

Quote:

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Originally Posted by Funkstar

Just a guess....

;)

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But IS it that?

I've done a quick hunt about and couldn't see any reference to PSP being hardware assisted, but then the Corel site is useless.

Well it seems it does use DirectX according to a usergroup post about having directx problems.

So i would assume it is using some kind of acceleration that at least benefits from the higher speed and bandwidth if not the extra memory as well.

I'd not thought of DX implementation other than Direct Draw.

I thnk that you guys are right on the bandwidth issue. It's not frame size...it's ram and controller speed.

I just can't find any reasonable documentation on what PSP uses DirectX for and what atributes of a card are going to speed it up.