The official answer
to this question is from the IE9 Platform Preview website:
Q. Does Platform Preview run on Windows XP?
A. No. Internet Explorer 9's GPU-powered graphics take advantage of new technologies available in Windows 7 and back-ported only to Windows Vista. These technologies depend on advancements in the display driver model introduced first in Windows Vista.
Q: Does the Platform Preview work on Windows XP?
Oh no. In IE9, hardware graphics acceleration is used by means of a video card, which uses new technologies that are available only in Windows 7 and ported only in Vista. These technologies depend on improvements in driver models first introduced in Vista.
This explanation from the very beginning seemed to me somewhat doubtful. Let's see.
What kind of technology are we talking about? The MS site
claims that IE9 uses the Direct2D API
for rendering, and this API cannot be implemented on XP due to a different driver model. Well, that's clear. But Direct2D is not the only way to do hardware accelerated graphics! We have DirectDraw
, we have the ability to use the surface of Direct3D - as renderers of many video players do. Is hardware graphics acceleration in the browser such a specific task that it can be solved only through Direct2D?
As it turned out, no. Chromium 7th branch copes
with the task of hardware accelerated graphics in XP without any support for Direct2D, while demonstrating greater performance than IE9 on Win7 on a computer of comparable configuration
(for those who do not know this test
, browsers without support for hardware accelerated graphics in similar conditions are given in it 2-3 FPS).
Configuration of the system with which the screenshot is made:
Athlon 64 X2 3800+ 2.0 Ghz
4 Gb RAM
Ati Radeon HD 4600, driver 8.702.0.0
XP SP3 Pro
Chomium startup string:
start chrome.exe --enable-gpu-plugin --enable-accelerated-compositing --enable-click-to-play --enable-gpu-rendering --enable-video-layering --enable-webgl --enable- accelerated-2d-canvas - enable-nacl
So, the absence of IE9 for XP should be understood as an exclusively marketing ploy, at the same time killing two birds with one stone: raise sales of new operating systems and popularize the new API.
PS: the chromium assembly
I used. Try it yourself
PPS: Firefox, as far as I know, also went along the path of Direct2D - in any case, no experiments with about: config in the last beta gave me any comparable result from the same test in Windows XP.
PPPS: From the
GPU-accelerated Chome blog