Pondering GAT
As I mentioned in the introduction, the introduction of Game Accelerator Technology in the new BIOS really transformed the IS7, and opened up intriguing (if cheesily named) settings that did wonders for the performance of the board. There are four settings for the GAT feature: Auto, Turbo, Street Racer and F1. Needless to say, these names don't tell you much about exactly what GAT is doing to get its higher performance.

Those of you who are familiar with Springdale and Canterwood know that the main difference between these two chipset is Intel's PAT, or Performance Acceleration Technology. PAT is a feature on Canterwood boards which improves performance by using faster timings inside the north bridge. If you read Damage's review of the 865PE chipset, you know two things: One, PAT can make a substantial difference in performance, and two, the 875P and 865PE north bridge chips are identical—the 875P chips are simply the best of the bunch, and are approved by Intel for usage with PAT enabled.

It wasn't long, however, before motherboard manufacturers started wondering if the 865PE chips could handle running with PAT enabled, too. Soon after the release of the 865PE and 875P, some motherboard makers figured out how to enable PAT on 865PE chipsets. Needless to say, Intel was not pleased, and word around the campfire is that they will come down hard on any manufacturer who claims to have PAT on their 865PE board. As a result, the motherboard makers have taken to calling their 865PE PAT implementations something other than PAT.

So is Abit's GAT Intel's PAT? Well, probably. I'm sure you'll be shocked to read that Abit is mum on this subject, offering no comment whatsoever, and it's likely we'll never hear the answer to the GAT PAT question from them. Therefore, the best we can do is look at GAT's performance and features, and try to decide for ourselves. Some things for you to ponder: First, let's look at some excerpts from the release notes for a beta version of the current BIOS:

The default setting of the Game Accelerator is auto. This setting will automatically detect the hardware configuration for users.

"Turbo" will improve the gaming performance and it is independent with DDR memory modules. All users could enjoy the benefit of Game Accelerator via this mode; no matter what kind of DDR memory module installed.

"Street Racer" brings users higher gaming performance than what "Turbo" does; and DDR memory modules are stressed by aggressive timing settings in this mode. Not every memory modules can work flawlessly with it.

"F1" features most aggressive memory timings. If the memory modules could survive, "F1" will bring the system highest gaming performance.

With that in mind, let's analyze the four GAT settings. Though the first is Auto, I think the benchmarks will show that this should probably say Disabled instead. Auto implies that the system will choose from the other three performance options, but as you'll see, benchmark results from Auto don't match any of the other three options. Next up is Turbo. We already know that Intel's PAT modifies timings within the north bridge memory controller without modifying the timings of the memory itself. Abit states that Turbo should work with any memory, which implies that it's not modifying the memory timings, either. If Abit's GAT feature is enabling PAT, it sounds like Turbo is the setting to do it.

The obvious question at this point: If Turbo is Abit's answer to PAT, then what are Street Racer and F1? Based on the notes above, my suspicion is that these are PAT combined with more aggressive memory timings. Street Racer is likely some mild memory tweaks that nonetheless might not work on lower quality DDR400. F1 turns the timing screws down another notch, making its RAM quality requirements even more stringent.

Admittedly, this is all theory, but it's a theory we can hopefully test with benchmarks. When you're looking at the results, look at the relative performance first between the Intel 865PE and 875P boards, then between the Auto and Turbo settings on the IS7. If the theory is correct, the performance increase going from Auto to Turbo should be similar to the increase going from the 865PE to the 875P. With that in mind, let's take a look at the benchmarks.