4670 Crossfire - The secret to budget gaming? Page: 1
Introduction

CrossfireXWhen the HD 4670 arrived on the scene several months ago everybody knew that it wasn't going to be about raw gaming power and high resolutions. Priced at less than a meal for two at your favourite restaurant (providing that's not McDonalds) and kitted out with a HDMI port (at least in the case of our Gigabyte model), the card was undoubtedly an ideal candidate for the HTPC scene. However, in the battle between NVIDIA and AMD to bring us graphics cards with the most features at the lowest price points, one intriguing feature was added to the HD 4670 - a Crossfire connector.

In many ways this seems little more than a gimmick, after all Multi-GPU setup's are often considered the next step up for enthusiasts who already own the fastest graphics card on the market and want to run games at ludicrously high resolutions or maybe even simply extend their e-peens. Placing two low-end cards in Crossfire would surely just be a waste of money much better invested in a single mid-range card, wouldn't it?

With the HD 4670 priced at around £55-65 in most places, snapping two up for a Crossfire configuration brings you into the £120 territory of the HD 4850. As we already know the HD 4850 is certainly no slouch when it comes to gaming, and with 1GB models readily available, any potential advantage a pair of 512MB HD 4670 cards may have had in on the additional memory front is certainly negated.

Specs Comparison

Things start to look even more bleak for the HD 4670 when we put it alongside some if its closest relatives. As we can see from the charts above, the 4670 has less than half the stream processors of the 4850, a crippled 128-bit memory interface and a lower number of texture units. All of this results in less than half the pixel pushing power of the HD 4850 (480GFlops vs 1000GFlops) suggesting that even if Crossfire was to be 100% efficient (which it's certainly not), a pair of 4670's would still fall short of the performance of a single 4850.

But of course, we're not going to let any of this deter us from having some fun with potentially one of the cheapest Crossfire configurations the world has ever seen. So join us over on the next page where we lay down the test configuration followed by a healthy selection of benchmarks.



4670 Crossfire - The secret to budget gaming? Page: 2
Test Setup

A common mistake made when benchmarking graphics cards is that the rest of the PC system isn't sufficient enough to test the GPU to its limits. This results in a bottleneck situation, where the system can only run at the speed of its slowest component. For this reason, the test configuration chosen below has been specially selected to give the 4670 Crossfire configuration plenty of headroom to produce the best results.

Test SetupCPU
Intel Core2Quad Q6600 2.4Ghz @ 3.6 Ghz

Motherboard
ASUS P5E64 WS Evolution

Memory
Cellshock DDR2 PC-2 6400 5-5-5-18 @ 800mhz

Power Supply
Tuniq Ensemble 1200w

Graphics Drivers
NVidia Forceware 180.48
ATI Catalyst 8.12.72276

Operating System
Windows Vista 64bit SP1

A selection of games and benchmark suites has also been chosen to test each of the graphics cards used in today's review on several different game engines. Each graphics card configuration will be run at both low and high resolutions with varying levels of texture filtering to represent 17", 20" and 24" screen sizes.

3DMark05
1024x768 / 0xAA
1680x1050 / 4xAA
1920x1200 / 4xAA

3DMark06

1280x1024 / 0xAA
1680x1050 / 4xAA
1920x1200 / 4xAA

3DMark Vantage
Performance Mode
High Mode
Extreme Mode

ET:Quake Wars
1440x900 / High / 4xAA
1680x1050 / High / 4xAA
1920x1200 / High / 4xAA

Unreal Tournament III
1440x900 / DX10
1680x1050 / DX10
1920x1200 / DX10

Call of Duty 4
1440x900 / Max / 4xAA
1680x1050 / Max / 4xAA
1920x1200 / Max / 4xAA

Farcry 2
1440x900 / Max / 4xAA
1680x1050 / Max / 4xAA
1920x1200 / Max / 4xAA

Racedriver GRID
1440x900 / High / 4xAA
1680x1050 / High / 4xAA
1920x1200 / High / 4xAA

Crysis
1440x900 / DX10 / High / 4xAA
1680x1050 / DX10 / High / 4xAA
1920x1200 / DX10 / High / 4xAA

During the benchmarking phase, we will be using the following prices extracted from US retailer newegg.com on 15/01/09 to produce our CPF (Cost Per Frame) graphs. Please remember that these graphs are static and only represent a snapshot of the market at the time of this review.

2x Gigabyte HD 4670 (GV-R467D3-512I) - $159.98
Gigabyte HD 4850 Overclocked (GV-R485OC-1GH) - $138.00
HIS HD 4870 IceQ 4+ 1GB Turbo - $239.99
Zotac GTX260 (216) 896MB - $269.99


Overclocking

Using the "Auto-Tune" facility built into the ATI Overdrive™ driver control panel, the maximum overclock we were able to obtain from the Gigabyte HD 4670's in Crossfire was 765MHz on the core and 1050MHz on the memory. This is quite a small increase over the 750MHz / 1000MHz stock values, but in all honesty we weren't expecting a card aimed more at the HTPC market to be an overclocking monster.

Gigabyte HD 4670 overclock

Testing the card at both its stock and our overclocked settings in 3DMark Vantage Performance mode reveals that this small increase in speed on the core and memory certainly wasn't fruitless and managed to bag us over 200 additional points.



4670 Crossfire - The secret to budget gaming? Page: 3
3dmark

3DMark is a popular synthetic gaming benchmark used by many gamers and overclockers to gauge the performance of their PC's. All 3DMark runs were performed a total of 5 times, with the highest and lowest results being removed and an average calculated from the remaining 3 results.

3DMark05 Results

3DMark06 Results

3DMark Vantage Results
 

Result Discussion

3DMark05 sees a good start for the Gigabyte 4670 Crossfire configuration with the power of two cards managing to not only beat the Gigabyte HD 4850 1GB, but also the overclocked HIS 4870 and the Zotac GTX260 216 too! This trend continues as we enter the higher resolutions with the 4670 setup once again beating the 4850 and GTX260 cards and only losing out to the 4870.

However, the smug smile is soon wiped off the 4670 Crossfire's face once we enter 3DMark06 with both the HIS 4870 and the Zotac GTX260 pulling way ahead of the discount duo. The 4850 unfortunately just can't compete at lower resolutions and only manages to regain ground once the resolution is bumped to 1900x1200 with 4x AA.

Moving on to the grueling 3DMark Vantage, both the 4850, 4870 and GTX280 get a chance to point fingers and laugh at the 4670 Crossfire setup as it falls completely flat on its face. Granted that PhysX acceleration comes into play here, but in most cases the Zotac GTX260 comes within a whisker of doubling the 4670 Crossfire's results.



4670 Crossfire - The secret to budget gaming? Page: 4
Call of Duty 4

Call of Duty 4 is a stunning DirectX 9.0c based game that really looks awesome and has a very full feature set. With lots of advanced lighting, smoke and water effects, the game has excellent explosions along with fast game play. Using the in-built Call Of Duty features, a 10-minute long game play demo was recorded and replayed on each of the GPU's using the /timedemo command a total of 5 times. The highest and lowest FPS results were then removed, with an average being calculated from the remaining 3 results.

CoD4 Results

CoD4 CPF Results

 
Crysis

Crysis is without doubt one of the most visually stunning and hardware-challenging games to date. By using CrysisBench - a tool developed independently of Crysis - we performed a total of 5 timedemo benchmarks using a GPU-intensive pre-recorded demo. To ensure the most accurate results, the highest and lowest benchmark scores were then removed and an average calculated from the remaining three.

Crysis Results

Crysis CPF Results
 

Result Discussion

Once again things start off looking really good for the 4670 Crossfire configuration in CoD4 with the only competition at lower resolutions coming from the GTX260. As the resolution is increased the 4870 is given a chance to catch up, almost matching the dual 4670's score, but unlike we previously predicted the 4850 is absolutely nowhere to be seen and sits in a firm last place. This certainly bodes well for the CPF (cost per frame) scores, with the 4670 Crossfire setup showing the best value for money out of all the cards.

Crysis on the other hand, much like the 3DMark Vantage benchmark; puts the 4670's through hell. While it has to be said that at the lowest resolution of 1440x900 the cards are only within a few FPS of the 4850, once the resolution is bumped up the whole experience becomes a slideshow almost to the point where we could have closed FRAPS and counted the time in between each frame ourselves.



4670 Crossfire - The secret to budget gaming? Page: 5
ET:Quake Wars

ET:Quake Wars is a follow-up game to Wolfenstein:Enemy Territory developed by Splash Technology. Using a modified version of id Software's Doom 3 engine along with Mega rendering technology, the game promises high resolution textures, fast gameplay and plenty of explosions. Using the built-in recordNetDemo and timeNetDemo commands, we recorded a 5 minute online gaming session and played it back a total of 5 times at each resolution, calculating the average FPS from the median three results.

ET:Quake Wars Results

ET:Quake Wars CPF
 

Far Cry 2

FarCry 2 is based upon the Dunai engine developed by Ubisoft and takes advantage of multi-core processors along with support for the DirectX 9 and DirectX 10 API. Running the Far Cry 2 benchmark tool the test was run 5 times with the highest and lowest scores being omitted and the average calculated from the remaining 3.

Far Cry 2 Results

Far Cry 2 CPF
 

Result Discussion

In ET:Quake Wars the 4670 Crossfire configuration and 4850 are practically indistinguishable from each other, matching FPS results across all three resolutions. However, as the 4670 configuration comes in at around $20 more than a single 4850, the CPF results go slightly in favour of the HD 4850. Interestingly though, the 4670 setup still manages to offer much better value for money than the HIS 4870 and Zotac GTX260.

Far Cry 2 tells a similar story to most of the results over the previous pages, with the Dual 4670's putting in a good show at 1440x900 but then falling into last position once the resolution is increased and filters applied. That said, there really is only a couple of FPS between the 4670 Crossfire and the 4850, but as we already know the 4670 setup has to do much better than that if it's going to compete on the CPF charts.


4670 Crossfire - The secret to budget gaming? Page: 6
GRID

Race Driver: Grid is a visually taxing game that presents a challenge to any graphics system. Results were recorded using FRAPS to log the average FPS over a 2 minute race. To ensure consistency, the same track, car and general path of travel was used in each of the 5 benchmark runs for each graphics card, with an average FPS being calculated from the median three results.

GRID Results

GRID CPF
 

Unreal Tournament III

Unreal Tournament 3
the latest game in the long running Unreal series from Epic Games and Midway. The game uses the latest UE3, which combines fast gameplay along with high quality textures and lighting effects. All benchmarks were performed using UTbench with a fly-by of the DM-BioHazard map. As usual, all benchmarks were performed 5 times, with the highest and lowest results being removed and an average calculated from the remaining three.

UT3 Results

UT3 CPF
 

Result Discussion

Finishing up with GRID and Unreal Tournament III, the 4670 Crossfire configuration just can't keep up with the other cards in the test even at lower resolutions. However, while UT3 was certainly playable at 1900x1200 with an average FPS of 113.65, GRID on the other hand was not. This may sound strange considering the 4670 Crossfire setup was pushing out close to 60FPS average, but with a minimum FPS of just over 20FPS, the with the fast paced racing style and debris from other cars was clearly taking its toll on the Crossfire configuration making gameplay quite awkward.

In terms of cost per frame (CPF) the 4670 Crossfire configuration comes in just a little more expensive than the 4850, but still better value for money than the 4870 or GTX260.



4670 Crossfire - The secret to budget gaming? Page: 7
Conclusion

Gigabyte HD 4850 CardsSumming up the performance of a 4670 Crossfire configuration is certainly no easy task. In benchmarks such as Call of Duty 4 and 3DMark05 it performed admirably often beating the HD4850 1GB and in some cases even the factory-overclocked HD4870. In most other benchmarks the Crossfire configuration went head-to-head with the HD4850 often winning at the lower resolutions but choking once high resolutions or texture filtering were applied. 3DMark Vantage and Crysis on the other hand; were a total disaster, with the Crossfire setup showing serious signs of strain and producing almost laughable results in comparison to  the 4800 series cards and of course the PhysX enabled GTX260.

In terms of value on our CPF scale the HD 4670 setup positioned itself just above the HD 4850, but still quite a way below the HD 4870 and GTX260 in most benchmarks. Add to this the inconvenience, additional noise and flakey support for Crossfire among game developers and it's pretty much safe to say that two 4670's in Crossfire are NOT the secret to budget gaming and a better investment would be in the HD 4850.

However, if you already have a HD4670 in your machine and are looking for a way to crank up the gaming performance at minimal cost, dropping in an extra 4670 will certainly achieve the desired effect and allow you to game alongside the 'big boys'....well at least in a handful of titles.


The Good
- Some games show great improvements.
- Cheap way to substantially improve gaming performance if you already own a single HD 4670.

The Mediocre
- Takes up extra space inside your system.
- Generates more heat and noise.
- Costs (a little) more than a single HD 4850.

The Bad
- Performance in some games is terrible.
- Cannot compete with the HD 4850 at high resolutions in most games.




Thanks to Gigabyte for providing the HD 4670 and HD 4850 cards for todays review.
Discuss this review in our forums.