Gigabyte GeForce 6600GT - An AGP Alternative

Today we are taking a look at a Gigabyte graphics card for the still present and active AGP graphics card market. We're looking at an AGP version of the popular nVidia GeForce 6600GT core. Read on as we take a closer look at the graphics card and how Gigabyte went about turning this PCI-Express chipset into an AGP edition and as well as the performance differences between both cards.
Published Mon, May 2 2005 11:00 PM CDT   |   Updated Tue, Apr 7 2020 12:26 PM CDT
Rating: 90%Manufacturer: Gigabyte

Gigabyte 6600GT AGP - Introduction

IntroductionThe nVidia 6600GT GPU core has been the biggest success story for nVidia in quite some time. The GeForce 6 family has become a breath of fresh air for a company struggling to keep its biggest competitor, ATI, off their back.When ATI released the Radeon 9xxx, GeForce FX certainly took a nose dive in performance and sales, especially due to the overheating cores and vacuum sounding coolers that were needed in order to keep the card cool. GeForce 6 made a huge power boost for the nVidia team, though there has been some controversy with its 6800 family and the broken support for Purevideo, but we won't get into that today - we are here to talk about the most popular core, the 6600GT.6600GT was introduced to the market as the first PCI-Express native solution for the mid-range graphics card market, and hasn't it grown from there. Designed on the latest 0.11um process with support for SLI, it has become the video card of choice. Designed to work with PCI-E from the start, nVidia used its HSI bridge in order to convert the PCI-E signals the core uses into AGP signals that various AGP enabled motherboards still use. This has now made the 6600GT a possibility on AGP enabled systems.Today we take a look at Gigabyte's retail offering of the 6600GT AGP edition and compare it to the reference video card to see just what (if any) speed advantages have come since the introduction of the reference card and then compare it to the PCI-Express edition.

Gigabyte 6600GT AGP - Specifications and The Card

Specifications of the GV-NT66GT-128DGPU/VIP: nVidia GeForce 6600GT GPUBus: AGP Bridged through HSI BridgeGraphics Bus: 128bitMemory: 128MB GDDR3Memory Bus: 128bitMonitor Connections: 1x 15pin D-Sub. 1x DVI-I Digital InterfaceTV Support: HDTV, S-Video, RCA output through selector boxSupports Multiple Monitors: Yes (nVidia nView)Hardware Monitor Support: YesSoftware Bundle: 1 Game + Power DVD.Core Clock: 500MhzMemory Clock 900Mhz (450Mhz DDR)The Card and Package
Gigabyte packs their 6600GT AGP edition in a very similar box to what the PCI-E version ships; however, on the front and back it clearly states this version is AGP, so no confusion should arise when purchasing the card in a retail shop.Inside the board a very liberal package in supplied, as Gigabyte wants to keep the cost of the card down as much as possible. Inside you get your user manual, Driver CD, full game CD (varies depending on what revision of the card you get), Power DVD 5 CD, TV breakout box and power splitter cable.
These days it is very hard to find a graphics card that differs from the reference design that nVidia or ATI set out. Gigabyte has based the 6600GT AGP edition around the reference design for two reasons. 1) Trusted and stable layout and 2) no R&D needs to go into the card for PCB layout changes, keeping costs to a minimum for production. The PCB though is a blue colour rather than the green used by nVidia for reference.The coolers used are designed by Gigabyte for a slightly better thermal dissipation of heat. The cooler on the GPU is angled due to the layout of the GPU chipset. Below that a smaller passive cooler is attached to the HSI bridge in order to keep this little fellow running at a safe temperature. While it appears the two coolers are connected they are both separated. A nice idea would be a cooler that fits on both to actively cool the HSI and GPU. With the coolers removed you can see how closely the card resembles the reference design. Being an AGP based card, there is no support for SLI due to the lack of dual AGP based boards.
The driving force is the nVidia GeForce 6600GT. This chip has become one of the biggest sellers in the mid-range market. Able to hold its own against the ATI X700 series with the ability to pair up with an additional 6600GT (PCI-E only) to increase the graphics performance, its no wonder that the 6600GT is making a good name for itself.
Memory wise, the same Samsung 2ns BGA G-DDR3 chips which power Gigabyte's PCI-E 6600GT and nVidia reference card are used. These chips are able to handle speeds up to and beyond 1GHz, so overclocking on this card via memory should be just as good as the Gigabyte PCI-E version.- Changes from the PCI-Express editionDue to the 6600GT being a native PCI-E solution, nVidia needed to convert the signals that the GPU produces into AGP. Fortunately the HSI bridge chip was sitting on the back lot with nVidia which was originally designed to convert AGP based video cards over to PCI-E during the beginning of the PCI-E era. The PCX series that the chip was used on was avoided like the plague due to stability problems trying to run the AGP based chips at speeds beyond their rated maximum. However, this chip could be used to convert the faster PCI-E back to AGP without having to overclock buses, which is what nVidia has done, allowing its PCI-E based GPU's to run seamlessly on AGP systems with one simple bridge. The HSI bridge needs to be cooled by a heatsink as running the buses through this small chip does tend to make it quite hot to the touch, a joint cooler with the GPU for active cooling would have been a better idea.
This is definitely a difference between the AGP and PCI-E versions. Based on a PCI-E bus, the 6600GT doesn't require an additional power connector. This is because of the revised power draw that the PCI-E can deliver. On the PCI-E bus, up to 75 watts is available to the video card, whereas on AGP 45 watts is the maximum that any card can draw. Obviously the 6600GT fits in the middle here as a 4 pin Molex connector appears on the AGP edition where no additional power is needed on Gigabyte PCI-E edition.OverclockingWe are pleased to report a great overclocking experience with this card. Being based on many of the PCI-Express based components, we were expecting to see speeds comparable to the PCI-E based cards. We managed to not only hit the PCI-E default clock speeds but exceed them. Coolbits was used to unlock the overclocking control panel in the Foreware drivers. With a default core clock of 500MHz and memory clock of 900MHz DDR, we managed to hit 720MHz on the core and 1.2GHz on the memory - the exact same as our PCI-E version reached - which is an excellent result.

Gigabyte 6600GT AGP - Benchmarks - Test System Setup and 3DMark Series

Test System SetupPCI Express SystemProcessor: Intel Pentium 4 560 (800MHz FSB) (Supplied by Spectrum Communications)Memory: 2x 512MB DDR2-533 Mushkin (Supplied by Mushkin)Hard Disk: 2x Maxtor Maxline III 250GB RAID 0Motherboard: ASUS P5AD2-E Premium (Supplied by ASUS)Operating System: Microsoft Windows XP SP2 and nVidia Forceware 71.84AGP SystemProcessor: Intel Pentium 4 560 (800Mhz FSB) (Supplied by Spectrum Communications)Memory: 2x 512MB DDR-533 OCZ (Supplied by OCZ)Hard Disk: 2x Maxtor Maxline III 250GB RAID 0Motherboard: ASUS P4C800 Deluxe (Supplied by ASUS)Operating System: Microsoft Windows XP SP2 and nVidia Forceware 71.843DMark03Version and / or Patch Used: Build 360Developer Homepage: http://www.futuremark.comProduct Homepage: It Here
3DMark03 is the latest version of the highly favored 3DMark series. By combining full DirectX9.0 support with completely new tests and graphics, 3DMark03 continues the legacy of being industry standard benchmark.Please Note: Due to recent events with the 3DMark03 series, we are adding results purely for those who are still in favor of 3DMark03. These results should not be taken too seriously and are only added for interest sakes.
3DMark03 shows that at default clocks the 6600AGP isn't quite as fast as the PCI-E version, however, when overclocking the card to the PCI-E speeds, there is not much difference in speed despite the platform changes.3DMark05 Version and / or Patch Used: Build 120Developer Homepage: Product Homepage: Buy It Here
3DMark05 is the latest version in the popular 3DMark "Gamers Benchmark" series. It includes a complete set of DX9 benchmarks which tests Shader Model 2.0 and higher. For more information on the 3DMark05 benchmark, we recommend you read our preview here.
3DMark05 confirms the same results at 3DMark03.

Gigabyte 6600GT AGP - Benchmarks - Doom 3

Doom 3Version and / or Patch Used: UnpatchedTimedemo or Level Used: Custom TimedemoDeveloper Homepage: Product Homepage: http://www.doom3.comBuy It Here
Doom 3 is the latest game to hit our test lab and is one of the most intensive games to dates. With our own custom time demo we are able to give a realistic rating on what kind of FPS you will be achieving.For more information on benchmarking Doom 3 we recommend you check out our extensive article regarding it here.
Doom 3 is one of the most graphically intense games available, when clocked at default speeds, the lower memory clock does hamper the AGP card, however, a simple overclock to PCI-E speeds shows almost identical scores - DDR-2 memory on the PCI-E platform would help to raise the scores in the PCI-E favour.

Gigabyte 6600GT AGP - Benchmarks - Half Life 2

Half Life 2Version and / or Patch Used: UnpatchedTimedemo or Level Used: Bench'emAll DefaultDeveloper Homepage: Product Homepage: http://www.half-life2.comBuy It Here
By taking the suspense, challenge and visceral charge of the original, and adding startling new realism and responsiveness, Half-Life 2 opens the door to a world where the player's presence affects everything around him, from the physical environment to the behaviours even the emotions of both friends and enemies.We benchmark Half Life 2 with our own custom timedemos as to avoid possible driver optimizations using the "record demo_name" command and loading the timedemo with the "timedemo demo_name" command - For a full list of the commands, click here.
Half Life 2 doesn't show much difference between the two cards even at the AGP's stock speeds.

Gigabyte 6600GT AGP - Benchmarks - High Quality AA and AF

High Quality AA and AFAll tests were run with 4 times FSAA and 16 times Antistrophic Filtering enabled with the screen resolution set to 1024 X 768.1024x768 was chosen as it is still the preferred playable resolution with these settings enabled.
At default clock speeds, the lower memory speed of the AGP version takes its toll on the FPS. When clocked to PCI-E speeds, the cards are almost identical; it's only the DDR-2 advantage that gives the PCI-E a better score.

Gigabyte 6600GT AGP - Final Thoughts

Final ThoughtsHowever you look at it, the nVidia 6600GT be it in AGP or PCI-E form, is certainly a fantastic buy.Designed from the ground up as a PCI-E native GPU, nVidia has used its HSI bridge to give AGP users the benefits of the powerful 6600GT architecture. There are a few limitations to the AGP version. First you don't have the full bus speed that PCI-E does; however, due to the architecture of the GeForce 6 series, PCI-E doesn't really render any great benefits other than future proof. The most notable loss with the 6600GT in AGP is SLI. Due to limitations of the AGP architecture, you are unable to run the AGP version in any form of SLI. When bridging the chip, SLI is rendered unusable, so you are restricted to one card, whereas PCI-E gives you the option of adding a second later on.Overall Gigabyte has done a fantastic job producing a card that not only looks good but performs well as well as keeping the price as low as possible for a 6600 card.We were impressed with the overclocking of the card due to the use of PCI-E memory modules and the PCI-E core, so there is no reason you can't clock this baby to PCI-E speeds for that extra performance boost.Pros- Impressive overclocking- Fast memory used- Price- Good performanceCons- No SLI support but not by fault of GigabyteRating - 9 out of 10 and TweakTown's "MUST HAVE" Best Value Award

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