Exploration into Overclocked AGP Graphics

Introduction

It has been a short period of time since we released the shocking information about Intel’s i820 being inferior the old yet nimble 440BX chipset (Showdown at 133 MHz FSB - Part 2, The Real McCoy) that could run a 133 MHz FSB setting. After heavy evaluation of each chipsets’ performance, the conclusion was that the 440BX was the best solution when using a Coppermine processor for the performance and price as long as you had no issues running the AGP and BX chip at higher than specified speeds. The biggest issue involved here if you are that serious is the fact that graphics cards may not like running at such a high AGP speed (89 MHz vs. 66 MHz). This is what stemmed this particular article. What graphics cards could boot at this speed ? Which cards could run reliably ? Would it cause the temperatures to increase on the card itself ? What would the gains be ? All these questions needed answers so we’ve run a bunch of tests to see who made the cut, and who didn’t.

The Questions

So there are a few obvious questions we needed to answer before pushing the 133 MHz FSB setting on the 440BX motherboard. First things first, you have to have a reliable 440BX that can run the 133 MHz FSB setting and memory that can do this as well, preferably CAS latency 2 memory. Once you have those two issues taken care of, you are now faced with which video card to choose. Currently, we know that the reference GeForce 256 has no issues running at the overclock setting of 89 MHz but this doesn’t mean any flavor of GeForce 256 will as board designs vary. We also don’t know how other graphics chipsets will react. We need to find out not only if they’ll work but if they can handle the stress for an extended period of time if we’re to deem them stable.

The Testing Methodology

Testing each card would be done on a P3 800/133, Asus P3B-F, PC133 CAS 2 (and 3) memory, Netgear FA-310TX network card and WD Expert 418000 HDD. Each card would be tested by booting it, loading the OS, and then finally, running Quake3 for 30 minutes while connected to a server full of bots. Any crashes or failures would be noted and idle/working temperatures would be tracked to see how the added buss speed affected heat, if at all. Obviously if the card failed to even boot, no tests would be run and the card would automatically fail the test. It is possible that a card may boot, get into the OS yet fail to start Quake3 or run it with stability. These tests were run on CAS2 and CAS3 latency memory to see a comparison of the performance and stability of each. Technically, the memory timing shouldn’t matter to the video card but it’s good to check regardless.

The Test Subjects

With the performance parts in mind, I chose graphics cards that would most likely be used on this caliber of a system. I also tried various brands if the particular chipset was shipping from a range of companies. Here is the list of the cards tested :

With 15 cards total, less than half passed the full test. During the testing, basically all the boards failed during the boot process and not during the testing itself. If the board made it as far as the OS, it ran just fine. The most surprising part is that a given chipset didn’t always pass across the board. Variations in the design proved that some companies had designed the boards to deal with a greater AGP speed tolerance (or were just plain lucky). This doesn’t mean that the companies that failed obviously made a inferior design but didn’t (couldn’t) design the board to reach such high speeds. Remember, we’re talking about running the AGP 33% faster than normal. Let’s take a look at who did what.

Benchmark Setup