With the advent of the new 800mhz frontside bus (FSB) on Intel’s latest processors, the automatic assumption is that they must be faster than their 533FSB cousins. In many cases this is true, but let’s take a closer look at why and how.
First we’ll gauge processor performance; pound for pound, can the faster FSB get more work done? The test system was an Intel D865PERL motherboard, two sticks of Apacer PC3200 CL3 RAM, a Maxtor Diamondmax Plus 9 120GB hard drive and an MSI GeForce4 TI4200 4X 64MB video card. If you’d like to find out what the scores below mean, click here. I strongly suggest visiting this link before reading further because it will explain what is being tested and why the differences are the way they are.
Next, how is memory bandwidth affected by RAM frequency and the frontside bus speed? For this test I again used SiSoft Sandra 2003 Pro.
As you can see, the faster 800FSB can use about 30% more memory than the 533FSB can. Increased memory bandwidth leads to more efficient CPU-intensive calculations and higher framerates in 3D games. The more RAM bandwidth the CPU has to work with, the more speedy its operations will be. Considering the fact that all of the 800FSB processors have Hyper-Threading Technology built-in, the increased memory bandwidth is even more important because of the extended processing capabilities that HT provides. While it doesn’t exactly make one processor do the work of two, it does have the capacity to execute two instructions simultaneously. The more memory bandwidth available to the processor, the more the advantage of HT is shown.
Let’s take a closer look at just how 3D gaming is affected by the 800FSB and HT Technology. There are a lot of Internet rumors about negative gaming performance from HT-enabled processors. Unfortunately these rumors seem to stem from hardware review and editorial/gossip sites and that gives them more credence. As you can see below, HT Technology has little or no effect on in-game benchmarks and 3DMark.
So while there is a significant and noticeable difference between the 2.4B and the 3.0C, there is very little difference between the 2.4B and the 2.4C in terms of gaming performance. The 3.06B seems to be in a rough spot — it’s outperformed by the 2.8C in most areas due to the 800FSB’s higher memory bandwidth. There is a measurable difference between the 3.0 with HT enabled and the same CPU with HT disabled, but the difference is so small that it would be impossible to notice it in a real game. This testing procedure doesn’t take background processes into account; in other words, if you have antivirus software or other applications running in the background you’ll see HT make a positive difference in framerates. Newer games such as Aquanox 2 and Spellforce and others that are built on the Krass engine are designed with HT Technology specifically in mind and will get much better performance with a Hyper-Threaded CPU. So no matter what the other hardware sites say, my advice is to leave Hyper-Threading support enabled even if all you do is play 3D games; overall system performance will be significantly reduced in Windows XP as you can see here in the Sandra CPU tests:
So in effect, disabling HT on a 3.0C processor is almost like replacing it with a 2.6C.
Finally let’s take a look at how price factors into the equation. The following prices were taken from a wholesaler’s dealer price list as of 6/16/03:
In conclusion we can safely say that the 800FSB does make a significant difference in computing power and performance, and the small price difference makes it a great bargain considering what you’re getting for what you’re paying. For a new Intel system build don’t even consider the 533FSB — go for an 800FSB CPU and DDR400 memory. If you have any questions about RAM, feel free to join our moderated forums by clicking the Forums link on the left.
Copyright 2003 Jem Matzan. Verbatim copying and redistribution of this entire article are permitted without royalty in any medium provided this notice is preserved.