Januari 31, 2009

At the end of september 2008 AMD released two interesting low-budget graphics cards: HD 4350 and HD 4550. The HD 4550 got my attention because:

1. full decode ability for VC-1 and Mpeg2 and advanced HD-deinterlacing (see: Overview of GPU HD Video Processing)
2. hdmi-output with HD-audio
3. low power consumption (even less then Nvidia 8500GT)
4. passive cooling = silent

Some reviews confirm that this graphics card is a good choice for a htpc-system: bjorn3d.com, planetx64.com, hothardware.com, anandtech.com, pcgameshardware.com. When reading these reviews it is good to remember what you are looking for.

I am interested in the best quality of DVD playback and a silent PC (HTPC - Home Theater Personal Computer).

I am NOT interested in gaming.

Gigabyte GV-R455D3-512I

The HD 4550 comes in many flavours and not only with passive cooling: Sapphire (no hdmi-output), Club3d (with fan), Asus (with fan). But finally this one looked convincing: Gigabyte GV-R455D3-512I

Here you can find compatible components for the Shuttle SG33G5M, but at this moment the HD 4550 is NOT listed...

Gigabyte GV-R455D3-512I

DVI and HDMI

I used DVI-I (to HDMI) and HDMI (to HDMI) cables and attached them to my Samsung LE37M86BD full HD display. The Samsung has 3x HDMI (1 HDMI-input supports DVI to HDMI).

Using the ATI software and setting up the system was not easy. I am used to nVidia-software which is easy to use.

But I have to admit: there are many options to tune the graphics card using the Catalyst software!

Comparing DVI and HDMI

DVI is used mainly for connecting computers to the display. On my Samsung display I have less video options to adjust image quality compared to the HDMI-input.

HDMI is typical for connecting DVD-players. My Samsung display has extra options to adjust display: sharpness, color, tint and options to select another colorspace called xvYCC. With the Catalyst software of the HD 4550 I can select for the HDMI-output the wide colorspace called: YCbCr. The resulting image is so beautiful that watching movies over HDMI suddenly becomes preferable? It's a bit more complicated because there is also a wide colorspace called 'RGB wide' which results in about the same Image Quality.

Both connections - DVI and HDMI - are perfect. DVI is computer-based and has a RGB-colorspace. HDMI has an extended colorspace (YCbCr) and more options for adjusting colors om my Samsung display.

YCbCr
The colorspace YCbCr originates from the way movies are encoded on DVD's. Most important question: is it better? So far, when comparing YCbCr and RGB-wide colorspace, I have seen some color differences. YCbCr tends to have slightly more 'vivid' colors. But human skin tones are better with RGB-wide.

Turning on the xvYCC option on the Samsung introduces a color-shift!!! This is quite dramatic. A color like 'aqua cyan' (#00FFFF) becomes light-blue!

Conclusion:

HDMI-HDMI results in the best Image Quality with these crucial settings:

HD 4550: Pixelrendering: RGB-wide

Samsung (in Film-mode): colorspace: wide and xvYCC: off.

When the Samsung is set to 'Standard-mode' the colorspace options are not available.

HDMI and HD-audio

When using the HDMI-output there is also audio present (over hdmi)!

You have to look for the HD audio drivers yourself. The HD audio drivers are NOT included on the installation disc. HERE you can find the HD audio codecs.

HD audio: does it work? I don't know... My Samsung display has no HD-audio options, neither has my digital receiver. All I can do is connect an optical from the Samsung display to my digital receiver and it should pass-through Dolby/DTS. All I got was stereo...

Conclusion: I have to upgrade my digital receiver in order to benefit from HD-audio over HDMI. For now I use the SPDIF output from my computer to my digital receiver (Dolby digital and DTS).

Note: SPDIF from the computer is always available whether I use HDMI or DVI-output to my Samsung display.

Blu-ray playback

Is great! It's faster, smoother and with better deinterlacing compared to Asus EN8500GT

I have 3 specialised dvd-players: PowerDVD 7.3, Nero Showtime 4.3.9.0, WinDVD 9 Plus blu-ray

Movie/image quality

WinDVD is the best, PowerDVD comes close, Nero Showtime is slightly worse.

Nero: on some discs like Nature's Journey weird things happen.

One example of what is better on HD 4550 compared to EN8500GT: At the beginning of 'Batman Begins' there is a 'DC'-logo. This logo has a light-grey background. With EN8500GT this grey background is not smooth, it's striped. With HD 4550 it is a smooth light-grey gradient area. The same effect can be seen on 'Planet Earth' intro's.

Deinterlacing with PowerDVD and Nero is worse compared to WinDVD, probably due to less support for the HD 4550 deinterlace capabilties. The HD 4550 has much better deinterlacing compared to EN8500GT and again it offloads the cpu.

Processor and system stress

With Asus EN8500GT some blu-ray playback made the cpu-temperature rise so much that the cpu-fan started to spin-up for extra cooling. Of course this means: more and irritating noise.

With Radeon HD 4550 the cpu-offload for typical blu-rays is so significant that cpu-temperature remains lower. Also the GPU-temperature of the HD 4550 is lower which results in a lower system temperature.

So far I never experienced extra noise from the cpu-fan during playback of blu-ray!

* cpu-fan set to 'Ultra-Low' in system BIOS (about 1250 rpm)

* default GPU and Memory clock settings for Asus EN8500 GT (no overclocking with Gamer OSD)

Note: the temperature readings are from XPCtools. This software is not always functioning correct. The Catalyst software for the HD 4550 seems to interfere with XPCtools.

CPU off-load

The off-load of the cpu is clear to see for VC-1 (most used blu-ray video compression).

I did not notice any cpu-offload for Mpeg 2 or 4.

Power consumption

It's clear: overall power consumption with HD 4550 is lower:

* total system power in Watts: computer + power supply

Windows Experience Index base Score

The HD 4550 software has an 'auto finetune' option which tests the system for the best, maximum over-drive settings for 3-D applications. On this Shuttle the test resulted in the following maximum settings for 3-D:

- GPU: 640 Mhz

- Memory: 840 Mhz

Note: the HD 4550 automatically adjusts GPU and Memory speed depending on the active application. For normal operation like (wordprocessing, internet, email on 1 display, this means: GPU: 300 Mhz, Memory: 500 Mhz. When playing a DVD the speeds change to: GPU 600 Mhz, Memory 800 Mhz. For 3-D application and games it can use the overdrive settings of GPU: 640 Mhz, Memory: 840 Mhz (values on my system after 'auto finetune').

Windows scores are identical to Asus EN8500GT (when EN8500GT is set to highest speed using Gamer OSD). So much for 'scores'...

Windows Vista Index base Score with HD 4550 optimised 3-D settings: GPU 640 mhz - Memory 840 mhz:

Conclusion

The ATI Radeon HD 4550 is an improvement compared to the NVidia 8500GT graphics card.

Less power consumption, less cpu-load and lower temperatures are good for a HTPC-system.

DVD-playback is smoother, better. The hdmi + HD-audio options make this graphics card ready for the future (I can not take advantage of HD-audio at this moment).

HDMI-output on HD 4550 has extended colorspace (YCbCr and RGB-wide) options for improved color-display, which is good for watching movies AND photography. At this moment I prefer a HDMI-HDMI connection.

UPDATE april 24, 2009: The drivers from AMD work fine! I tried the (latest) version: Display driver 9.4 and Catalyst 9.4, both for Vista. It's necessary to update both the display driver AND the Catalyst software!