ATI Hits With Mainstream DX10 - HD 2600 XT


Product: ATi/AMD Radeon HD 2600 XT
Provided By: MemoryExpress
Price: MSRP $229.99 CDN


Over the past few months, nVidia has been walking away with the DirectX 10 market as they were the first company to launch DX10 hardware - even before there was a DX10 Operating System to run them on.  The truth is, nVidia has been mopping the floor with ATi, and currently has the fastest card on the market with the 8800 Ultra.  That being said, sales of the high-end cards are always very limited and mainstream cards sell greater volumes than high-end parts.  Again in this area, nVidia has been cleaning up with their mid-high 8800GTS 320MB and lately their 8500 GT and 8600 GT/GTS offerings.

Up until today, the HD 2900 XT was the only DX10 card offered by ATi/AMD but today they add more SKUs to the pot.  They are launched several flavors of RV610 and RV630.  We are looking at the RV630XT today - better known as the HD 2600 XT.  This card is the high-end of the mainstream parts and comes with 256MB of GDDR4 clocked in at 1100MHz (2.2GHz DDR).  The core is clocked at a screaming 800MHz and our unit doesn't even require an additional power connector.

We took a brief look at this card last week in a preview article, and today we will fill in the gaps that were left with that teaser.  Some of this review will cover data from the preview, but we will add more comments and insight as we've had more time to play with the HD 2600 XT.

 RV630XT - Front
(Click Image to Enlarge)


You'll notice that the card features the now standard dual link connectors for Crossfire, but what you don't see is the additional power connector.  Normally, cards of this length and beasts and require extra power to operate.  With the HD 2900 XT being such a power hog, I really expected the HD 2600 XT to need additional power as well.  This is a bonus as it will be much more efficient.  The card is manufactured using the 65nm process and this is efficient enough to use a mere 45 watts (spec) under load.  Hopefully the card will run nice and cool as well.


The back of the card shows that the board is designed to handle another 256MB of memory.  This allows board partners to add more memory to their own version.  While some may argue that more memory on a mid-range card is pointless, higher resolutions will benefit from the added memory.

RV630XT - Back
(Click Image to Enlarge)


Closer Look:

The cooler is powered by a four pin fan that is temperature and software controlled.  You can find third-party software that allows you to increase fan speed at different temperature levels to help your cards performance.  Although not recommended, you can also slow the fan down to provide even quieter cooling.  The fan is a "blower" style fan that sucks in area and blows in along the length of the fins and exhausts the hot air inside the case.  Depending on how much heat this card generates, that could potentially be a bad thing; especially if you have poor case ventilation.

 RV630XT - Fan Power
RV630XT - Fan Power
 RV630XT - HSF

The HSF itself is made from copper and aluminum.  The central area that contacts the GPU die is made from copper, while the remaining portion of the cooler is aluminum - including the fins.  Contact with the memory is made though thermal pads, and contact with the chips is very good.  This is beneficial as I would think the memory would get hot running at 2.2GHz!!

Card Specs & Overclocking:

The RV630 Core is based on the 0.065 micron process.  This is a much more efficient process than the older 0.08 micron that was quite "leaky" on the HD 2900 XT.  In our earlier tests with this card, it runs between 36C - 40C idle and into the low-mid 60's when running fully loaded.  The single slot cooler is quiet and the card is not audible over the rest of our test system.

  • GPU - RV630 - 0.065 Micron
  • 390 Million Transistors
  • 120 Vertex Shaders - Vertex Ver. 4.0
  • 8 Textures / Clock
  • 120 Pixel Shader Engines - PS Ver. 4.0
  • Core Speed - 800MHz
  • Memory Speed - 1100MHz
  • Fill Rate - 6400 MTexels / sec
  • Memory Bandwidth - 35.2GB / sec

The memory is Samsung K4U52324QE-BC09 memory that runs on a limited 128-bit memory interface.  There is 256MB of this GDDR4 that powers the card at an impressive 1100MHz DDR.  More information about the actual memory modules chips is below.

The K4U52324QE is 536,870,912 bits of hyper synchronous data rate Dynamic RAM organized as 8 x 2,097,152 words by 32 bits, fabricated with SAMSUNG's high performance CMOS technology. Synchronous features with Data Strobe allow extremely high performance up to 11.2GB/s/chip.

  • 1.8V± 0.09V power supply for device operation
  • 1.8V± 0.09V power supply for I/O interface
  • On-Die Termination (ODT)
  • Output Driver Strength adjustment by EMRS
  • Calibrated output drive
  • 1.8V Pseudo Open drain compatible inputs/outputs
  • 8 internal banks for concurrent operation
  • Differential clock inputs (CK and /CK)
  • Commands entered on each positive CK edge
  • Double pumping address
  • CAS latency : 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22 (clock)
  • Burst length : 8 only


Full specs and card info can be found at ATI here.

The RV630 is said to consume 40-45W and overclocking is very limited in the Catalyst "Overdrive" settings.  We have experimented with several different Catalyst revisions and have been using the new Catalyst 7.6 drivers for the past week.  These drives fixed a few graphic issues we were having and had actual overclocking options in the Control Center.  We tried the latest ATI Tool, and ATI Tray Tools, but those just crashed our system.

 Catalyst 7.6
Catalyst 7.6


ATi limits the Overdrive settings to 857MHz core speed and 1179MHz (2.36GHz) memory speed.  While these may not seem like much, our sample was only able to run 100% stable at 855Mhz / 1175MHz.  If we tried to run at the maximum settings provided, we ran into some benchmark crashing.  The core ended up being ramped up just less than 7%, and the memory clocked accordingly with just under a 7% gain.  Real world results shouldn't show much of an improvement.  We're not that excited.  We expected more from this card, and perhaps withan additional power connection, we could squeeze out more performance.  We also have to keep in mind that this is a sample card.  Regular retail cards may be entirely different in terms of overclocking potential.


HD 2600 XT Laid Bare:

This next section will just show you closer views of the card and how it's laid out.  We've taken pictures of most of the interesting features of this unit and you can click any of the thumbnails below for a full-sized image.

 RV630XT - Voltage Regulators
RV630XT - Voltage Regulators
RV630XT - Engineering Sample
RV630XT - Engineering Sample
RV630XT - Bare Board
RV630XT - Bare Board
 RV630XT - Core
RV630XT - Core
 RV630XT - GDDR4
 RV630XT - Dual DVI
RV630XT - Dual DVI


On the next page we'll take a look at our system specs and jump into some real benchmarking of the HD 2600 XT from ATI/AMD!

Test System & Info:

We tried to acquire a 8600GT or 8600GTS to compare with the HD 2600 XT for this review, but at the time, our local computer shop had everything sold, and a trip up to our supplier in Calgary revealed very limited stock of these cards due to popular sales.  Unfortunately we have to post up the scores of the RV630XT all by themselves, but we hope to get some mid-range nVidia cards in the future and will compare the results at that time.  For now, our test system is listed below.

  • Intel Core 2 Quad Q6600 - Stock
  • Radeon HD 2600 XT - Stock (800/1100)
    Overclocked - (855/1175)
  • MSI 975X Platinum Motherboard
  • 2GB PC2-8500 Ballistix Tracer at 800MHz 4-4-4-12
  • Windows Vista Ultimate 32-bit
  • Catalyst 7.6 drivers


Thanks to the kind folks at AMD, we were able to grab the 7.6 drivers early and complete all of our benchmarks using these latest drivers.


Let The Benchmarking Begin!

If you read our preview, you'll notice the 3DMarks are slightly different, and that we've actually manged to run Lost Planet.

As requested by some reader feedback from the preview article, we have managed to do some overclocking (although minor) and post the results alongside the stock clock speeds of this card.  Although the clock speed increase is only 7%, it offers measurable performance increase in some situations.  I say "measurable" with caution, because although it can be measured, it probably isn't noticeable.

(Click Image to Enlarge)


A 7% clock speed increase yields a 4% increase in 3D Mark 2003.  Nothing much to brag about, but the card does break 15,000 points in our test system.

Next we jump right into 3D Mark 06, as we are unable to install 3D Mark 05 on any of our Vista test systems.  Repeated attempts have always failed, even with UAC disabled.

(Click Image to Enlarge)


Once again we are seeing a mere 4% improvement in 3DMark scores, but perhaps real world games will show a difference.  Take a look and the benchmarking continues!

DX10 Benchmarks:

As this is a DirectX 10 part, we want to focus this article on DX10 gaming on this mid-range card.  DX10 calls for a previously unheard of number of particles, shaders and operations, and mid-range cards can struggle in this situation.  Although DirectX 10 hardware has been around for quite a few months, as has a supporting Operating System, DX10 games are hard to come by.  We heard rumors that Shadowrun, Halo 2, and Flight Sim X would all be DirectX 10 titles, but they are not.  We could only grab three actual games that offered any kind of DX10 support and have included these in our review.


Company of Heroes:

Company of Heroes is an RTS that has an amazing level of detail.  DX10 support was added with the 1.7 patch and we've got everything patched up and ready to go in this DX10 RTS.

Company of Heros
(Click Image to Enlarge)


At 1024x768 with default settings, the game is very playable and averages over 57FPS in the built-in benchmark.  Overclocking doesn't yield and benefit at 1024x768, but does add a couple frames per second at higher resolution with more eyecandy turned on.  This is where the card shows its 128-bit memory limitation.  Higher resolutions with more detail bog the card down - at least in CoH.


Call of Juarez:


One of the games that caught my eye through testing was the new "Western" - Call of Juarez.  In this game you can choose one of two players that have a completely different impact how the story plays out.  Much of the game takes place outside and the level of detail with the DX10 benchmark demo is amazing.

 Call of Juarez
(Click Image to Enlarge)


I spent some time playing though the DX9 version of the game before I patched it up and ran the DX10 demo/benchmark.  DirectX 9 gameplay occurs around 36-42FPS, but bringing on the DX10 goodness changes things.  At 1024x768 the RV630XT stuttered to a 18-ish FPS, and increasing the resolution to 1280x1024 and 1600x1200 brought the system to a crawl.  This is where I wish I had an 8600GT/GTS from nVidia to compare the results.  Either way, you won't be doing much Call of Juarez in DirectX 10 on this card.

One of the earliest DX10 playable demos has been the Lost Planet Demo.  This is an interesting game that has a bit of a Half-Life 2 feel to it in my opinion.  We ran both DX9 and DX10 benchmarks under Windows Vista to see how much of a performance hit there is to run with the latest version of DirectX.

 Lost Planet
(Click Image to Enlarge)


At default detail and a default resolution of 1280x720, the game runs pretty decent on the HD 2600 XT.  The Snow level exhibits some minor stuttering, as does the Cave.  Overclocking only yields very small gains, and is unnoticeable during gameplay.  When we turn on the DX10 goodness, this get a little slower - in fact, the game runs about half speed and we are now seeing framerate averages at 17-21FPS.  In order to make the game playable on this card, you'd have to drop some eyecandy and the resolution.  In my opinion, that would negate the point of a DX10 gaming graphics card.

On the last page we'll take a look at some HD video playback and see just how ATi's AVIVO gets the job done.

HD Video Playback:

As computers have moved out of the office and into many rooms of our homes, the diversity and requirements of a computer have changed dramatically.  Although many people are still happy with an E-Machine, many others use the computer for a complete source of entertainment.  The computer is quickly becoming the center hub for our entertainment and as hardware and software have improved in this aspect, the Home Theater PC (HTPC) is becoming a popular addition to most home entertainment centers.  This is perhaps where the HD 2600 XT has the best fit.  As we've seen in our benchmarks, the performance of this card is lackluster in early DX10 benchmarks.  However, the HTPC arena is completely different.

Some HD 2600 XT cards are rumored to come with a HDMI (High Definition Multimedia Interface) connection, but our pre-release sample did not.  Instead it came with a pair of Dual-Link DVI connections and support for HDCP (High-bandwidth Digital Content Protection) content.  If you have a monitor or a large TV that supports HDCP as well, you can quickly turn you computer into a High Definition Multimedia Powerhouse.  We took this card and a nice shiny new Samsung SyncMaster 305T 30" LCD and had some fun.

We ran some HD Quicktime clips encoded with H.264 as well as some HD WMV video clips and looped them for a while in order to heat up the GPU and see how much processing power is handled by the AVIVO supporting HD 2600 XT Graphics Card.

 H.264 Decode Performance
(Click Image to Enlarge)


We grabbed some 2-3 minute Quicktime clips and played with the Quicktime player.  Each clip was looped for at least 15 minutes and CPU load and temperature averages were logged and the results averaged.  As you can see above, CPU load remained quite low, and the GPU heated up a fair bit above the 36C Stock Idle temperature.  At 1280x720, all these clips looked great with no stuttering, dropped frames or issues at all.


Next, we fired up some HD WMV clips and executed the same procedure.  Each clip was looped and data was recorded.  We managed to test both 1280x720 clips and 1920x1080 clips to compare the difference in CPU load and GPU temperature.  As you can see below, the 1080p clips caused higher GPU temperatures and took a bit more horsepower from the CPU as well.

 HDWMV Decode Performance
(Click Image to Enlarge)




This really shouldn't be that hard to draw a conclusion with this card, but I'm having a hard time giving it a rave review.  This is the first ATi card we've handled in a while, and while it does add DX10 support to it's list of features, the truth is that it's just plain slow in DX10 benchmarks.  While the card has an impressive number of shader units (120), it is crippled by 128-bit memory.  GDDR4 deserves to run free with at least a 256MB interface but it is severely lacking at such a low bitrate.  All that being said, if the price is right, it's still a decent card.

For current generation DirectX 9 games, the HD 2600 XT performs very well, and it does it quietly without complaints or instability issues.  For the casual gamer who wants to check out some DirectX 10 eyecandy, it may be a good buy.  If you are all about Vista, DX10 and games, you will want to look for a different graphics solution for your gaming rig, but you shouldn't count out the HD 2600 XT all together.  ATI's AVIVO and GPU processing power works very well for HD content, and although we weren't able to include HD-DVD content in the review, we did play around with an XBOX 360 HD-DVD drive on our system and it performed virtually identical to other HD content that we've shown above.  The HD 2600 XT is the best HD decoding card we've currently got here at BCCHardware.


  • DirectX 10 comes to mainstream ATI fans!
  • Doesn't require an additional power connector.
  • Decent DX9 performance.
  • Excellent HD Video decoding performance.
  • Very quiet single-slot cooler.

  • Slow DirectX 10 performance in current games.
  • 128-bit GDDR4 = Fast RAM but nowhere to run.

Because of the highs and lows of this card, it is a little hard to score, but we believe the numbers below are fair.  For only $100 more you can get an nVidia 8800GTS 320MB that should mop the floor in DX10 performance.  We hope to get a 8600GTS in the near future to compare cards in the same price point.  Due to time restrictions, we were unable to provide these numbers in this review. Rating
Software Pack:
Total Score 8.0


I'd like to thank MemoryExpress and ATI for sending this card our way for a review.  It's too bad that it's gone, as it would make a great card for HD Movies.

If you have any questions, comments or general feedback, please head on over and post it in our forum at the "Comments" link below.