Team Ars Technica Lamb Chop - Statistics and Benchmarking

When it comes to CPU's, there's no denying that the fastest X86 class CPU is a Xeon with 1M or more of L2 cache. The only problem with this is that they are simply too expensive to be realistic for most people (althought the price of PII 400 Xeons has come down very low). So the next best bet is the Intel PIII based off of the Coppermine core (this is the 'e' model with 256K cache). Why are these so great? Is it the 8 way associative cache? Is it the cool name? Nope- it's the fact that the .18 micron process allows us to overclock these things to insane levels. While the PII and older Katmai based PIII's are still good for Seti, the fact that they don't overclock as nice should be a deterent.
For those on a budget, the Celeron is also a good performer for Seti, assuming you get a slower rated Celeron (try a 366 instead of a 533), and that you overclock it to higher speeds, which will give you a higher bus speed. As for the rest of the x86 field, the Athlon is a surprising poor performer, apparently due to high cache latency, and the sub par FPU on the K6 series leaves it gasping for breath. Cyrix processors..well...you might get one unit every couple days.
You should be aware of the fact that the largest factor on Seti performance is the FSB (Front Side Bus) speed. This is because the working set for Seti (the memory that contains all the code which is constantly reused) is too large to fit in L2 cache sizes smaller than 1M. Therefore, higher FSB speeds help compensate for this by allowing the system to access the main memory much faster. That is why a 300MHz Celeron overclocked to 450MHz (100Mhz FSB) will smoke a 533 Celeron running at it's default 66MHz FSB.
Chipsets are important too. At least for those running Intel CPUs, I haven't seen too much difference with the AMD boards. Current Intel options include the popular BX chipset, the new chipsets, the i810, i820 and i840, and Via's offerings, the Apollo Pro 133a, and the Apollo Pro. The BX is a very good chipset, and it's very fast for Seti, due to good memory transfer rates. However, it's lack of 1/2 AGP dividers makes it sorta tough to keep everything stable up at 150+ MHz FSB speeds. The i810 and i820 have poor memory access times, and generally suck. Avoid them like the plague. The i840 looks to be a good chipset, but only if used with RDRAM, instead of the standard SDRAM. The problem there is that with the amount you'll spend on 128M of RDRAM, you could have built a second computer for Seti.
This brings us to the Via offerings. The Apollo Pro has horrible memory transfer speeds. Stay away from it. The Apollo Pro 133A, on the other hand, is a good chipset, with good memory transfer speeds, and the handy dividers we need for AGP and PCI slots. And it's scheduled to be coming out in a SMP (dual CPU) configuration this year. I'll have to get one of those to replace my aged SMP Celeron setup.
The last consideration for your new system is memory. Don't by cheap memory if you're planning on getting an overclockable CPU. You want to avoid the CAS3 PC133 offerings and get CAS2 instead. (CAS is a latency measurement) If you're planning on going really high with your memory, buy good quality mem like Micron, Siemens or Infineon. I have also heard very good things about TinyBGA (Tiny Ball Grid Array) DIMMs, which are supposed to generally be stable at 150MHz FSB speeds- which are possible with a good PIII 550.

General PC Hardware Settings
Here's a list of hardware settings to help speed up your system in general, all of which will decrease the amount of time that it takes Seti to complete a work unit:

For those of you with out multiplier locks, run at the highest possible FSB. Mavic proved this with his Pentium Pro, which in not multiplier locked. Running at 233MHz with a 66 MHz FSB, it took him 22:19 to finish a unit. He then set the same system to 240MHz with a 60MHz FSB, and it took an extra 2 hours to finish! Why? Seti appears to be very memory intensive, and the slower FSB settings will not be able to keep up with memory transfers between the CPU and the main system Mem. Don' t know if you can adjust your FSB? If you're running an AMD processor, you can adjust the FSB from the motherboard, although not all boards will allow you to run higher FSB's. For Intel systems, most 300MHz and faster systems are multiplier locked, so you can't adjust the FSB and still keep the same speed. However, if you're not already, you really should consider this next tip.
In your bios, make sure that the following settings are disabled; Shadow system Bios, Shadow video Bios; Cache video RAM. Depending on the type of Bios, this might also be called Cache *, instead of Shadow. It means the same thing though. All of these will cache information to the L2 cache, which will greatly slow Seti down. Users have reported time decreases of 1 hour or more with this tweak. This will also help speed up your system in general. Note: Cache video RAM should not be confused with AGP aperture size. This sets the amount of main system memory available for AGP.
If you have CAS2 RAM, make sure that it's set to 2 in the Bios. CAS stands for Column Address Strobe, and the number after it is latency. CAS3 is an older standard, most newer systems work fine with CAS2. This is a pretty obvious benefit. The faster you can access your mem, the faster Seti will run. And everything else for that matter.
Overclock your system! I really don't have to tell you the benefits of overclocking, I think I've covered that already. I'll just sum it up quickly. Faster is better. And this will help your entire system, not just your Seti times.
Win9x is awesome! Bet you don't hear that often! However, since the release of the 2.0 clients, Windows 9x have replaced Linux as the fastest operating system. Since that's what most people are running anyways, that's okay. But if you're still running Linux trying to squeeze units out a bit quicker..you should stop.
Running WinNT or Win2000? If so, I recommend that you visit Ars Technica's NT Tweakage tome. It's full of all sorts of good information that will speed up your system in general, which will in turn decrease your time in Seti.
Have you tried Linux? Most systems are showing sizeable decreases in time running under Linux vs NT, although they are slower now than Win9x. However, since not everyone can use Win9x (for example, it doesn't support my SMP), Linux is still a good alternative, although it's a daunting one. However, if you're a tweaker, and you like to try new things, this might be a good step for you. Also a big plus for the first time Linux user is that Red Hat has released V6.1, which has several improvements to help make the move to Linux less intimidating. For starters, the install process is now a GUI window, with a help section on the left side, guiding you through step by step. Also, RH sports DOS connectivity, meaning that a lot of the DOS commands you're used to using now work in Linux. So you can type dir and pull up a directory listing, instead of the Linux default of ls. Other advantages for Linux are that it's free, it supports SMP, and it's very good for increasing you geek factor, which is always desirable.

Seti Specific Information

Here are some things that you can do to speed up Seti directly. Since they don't fall under the general system settings, I've included them here.

Get the 2.0 client! Most users (being Win32 users) will see a nice boost with the 2.0 version of Seti. Also, the CLI now runs on most Win95 boxes, so you have no need to run the GUI client anymore.
Win32 users-run the CLI! Run the text only version (called i386-WinNT-cmdline on the Seti site), you'll see a large decrease in time. How much of a decrease? It really seems to depend on your system, but most people see between 5-10% faster times.
If you do run the GUI version, make sure that you've set the screen saver to blank after 0 minutes. This setting is located in the screen saver's properties. While the screen saver looks pretty, it will also consume HUGE amounts of system resources-leaving very little left for Seti. While I don't have a benchmark with the graphics on, I did turn it off on a friends system, and his average time went from 36 hours down to 14.