Before overclocking, I wanted to start by understanding how far each of the various chips could be overclocked with differing voltages and cooling methods. By going through a number of the online boards, I was able to create the following table of potential overclocks given different voltages and cooling systems versus the various AMD chips:
This chart is circa November 2002, and I found these to be very interesting results. Water cooling seems to give you something like 3-4 steps up over air. A Peltier-cooler will get you a couple more. A phase change cooler, such as a Prometeia, is good for even more. All told, you can boost the performance from air cooling by 6-10 steps. Compared to a stock chip, you can get as many as 10 steps ahead with suitable cooling and overclocking. Water cooling definitely delivers most of the "bang" available for the "buck".
KD-7 Overclocking Notes
When in doubt, study how the gurus operate...
Avoid "fast" cpu command decode, go with normal. You'll get a higher FSB.
1/4 divisor is only good for FSB 164, need 1/5 to get to 200.
One 200 FSB used: 2-2-6-2-2-1T and TwinMOS PC3200 DDR
Disk corruption is very likely above 200 FSB, some are reporting it at 190 FSB.
Set your Cpu OPerating speed to "User Define" and then set your FSB speed to approx what you know it will run at. For instance I run mine at around 200 so I usually start out at 180 x (multiplier varies for processor) I am running a 2700 so I set my mult. at 14 with my Prometia and I know I can boot into windows at that speed. Then set your voltage accordingly. On this board the ram and cpu voltage are run higher than usual. I set mine at 3.05 and 2.00 to start with. If your using air cooling than you will have to set them lower obviously and the same goes for your initial processor speed. Set ratio at 5:2:1. Now go to your "ADVANCED CHIPSET FEATURES Dram Clock/Drive Control and if your FSB is below 166 than you will have the option of setting the current Dram Frequency. If you are over 166 than it will default at 166. That is probbably the part that is confusing you.
If you are using decent ram you should be able to set your timings to the fastest timings available up to about 190 fsb. I know other people that have gone higher, but the 400 chipset has a problem with HD corruption above 200. Another thing is that you need to set your CPU fast command decode to Normal, because Normal=Fast on that board.
i wouldn't recommend pressing reset button at 180fsb cos then you'll have to clear cmos.
MrIcee's Advice: Clear your cmos.....on next boot enter the bios and set optomized defaults, hit F10 and reboot. On the next boot enter the bios and set it up to your liking. This finally straightened out multiple problems I had setting up the board....including mem timings not working. Now I 'm running max timings at 200Mhz+ FSB at only 2.95v. I am using the C8 bios as it seems the best by far...but it does report the board wrong.....makes no difference to performance. I leave my FSB set at 166Mhz to avoid the 180Mhz FSB or higher problems if I fail a bench(freeze) and have to reboot. Using SetFSB before opening 3DMark to set the FSB .
So, here are some handy tips so far (full review is on it's way!) Cpu is my usual unlocked XP2000, and mem is 512Mb Corsair XMS3200c2 Platinum, in 2nd Dimm Slot. ::WPCRSET Cpu Halt Commands:: Now, any settings for KT333 chipsets will knack u up. KT400 has it's own new settings... 2 of em... Open WPCRSET, disable any previous alterations, and add... D5 - 1E D2 - E8 So, that's your CPU temp down a bit... Next up, here's how I had the Bios setup... latest revision... (can't remember what that is offhand!) ::SoftMenuIII:: Type - UserDefine FSB - 205 Multi - 9 Ratio - 5:2:1 Error Hold - Disabled Bench Enhance - Disabled Voltages - User Defined CPU - 2.075v MEM - 3.15v ::Advanced Chipset > DRam Settings:: From the top... MANUAL 2 4 BANK 2 6 2 4 4 AUTO AUTO AUTO AUTO AUTO 3T DISABLED 1T 2T 3T 750ps
I run my memory timings set to Manual, CAS 2, 4 Bank, 2,6,2. I have also raised the memory voltage to 2.85v. These settings work great with my Corsair XMS3500. Now depending on which memory you have makes a big difference. If it is reading as PC 2700, my guess is that you have either Corsair XMS2700 or XMS3000. XMS3200 and XMS3500 usually read as PC3200 memory under Sandra. If this is the case, you will need to work much harder to achieve higher FSB speeds as you'll be pushing the memory harder. There are two things you should do. First, relax the memory timings to CAS 2.5, no bank interleave, 3,7,3 and see how high you can go FSB wise. If you find an improvement in how high you can go, we'll know it is the memory holding you back. If you have no luck with relaxed settings, make sure you've tried upping the memory voltages too. If relaxed memory timings do not get you any further, I'd suspect the R9700 or another component is holding you back. So the next thing to do is try another Vcard. XP2700+ @2.584; KD7-E; Water-Cooled; 226w TEC; Radeon 9700 Pro; 80w TEC 400/360
Start the overclock with FSB set to what your memory is designed for, and a multiplier that puts the CPU about 20% under default. Now crank the FSB until you hit instability, and back off. When you have the highest stable FSB, start cranking the CPU until you hit instability. You may need to increase vcore to keep the cpu stable, but watch the heat carefully.
MrIcee's plan to prevent HDD corruption at high FSB: If you do NOT run a RAID setup and have your hard drive(s) plugged into the boards IDE Ports, go into the bios and set the Hard Drive controller from ULTRA DMA to Pio mode on both channels. On Next boot into Windows, go into system properties and then Device Manager....under IDE/ATAPI ATA controllers...set primary and secondary to Pio mode only. Reboot. After these changes you'll now be able to run your KT-400 board to most any FSB without fear of corrupting your hard drives.
C8 bios is getting the best stability reports.
OPPAINTER runs his Radeon 9700 Pro at 490/358 overclock. JC Viggen at 495/393.
MrIcee's method for installing Via 4-in-1 drivers: How did you install them?? This can sometimes be the # 1 cause of gaming problems or anything videocard related. The proper sequence is as follows: Uninstall your videocard drivers Uninstall your previous 4 in 1's with their install package Use Reg Cleaner to clean up your registry automatically, and to also remove folders in the registry pertaining to your old 4 in 1 install and or Vid card drivers. Install the Hyperion 4 in 1's Install the videocard drivers of your choice This method of installing 4 in 1's has been xtremely successful for me, and I currently use the Hyperion's with great success on my KD7-Raid. Good luck my friend
The BorgCube Step-by-step Overclocking Blog
Parts is parts...
Except when we're overclocking. Let me review the list of special goodies I'm installing to bring up the BorgCube's performance:
Abit KD-7 motherboard: The fastest overclocking board as I write this, though devilishly finicky to make work right. NForce 2 cards are just beginning to beat it, but that's serious bleeding edge and Abit's card has no mounting holes for my water block at this time.
Athlon 2400+ XP: This chip is unlocked in software on the KD-7, relieving me of the trouble of unlocking by hand. It's also a good bit faster than my T-bird running at 1400MHz.
New DDR RAM: I'll probably buy Geil, but haven't ordered it yet. Good RAM is critical to FSB overclocking.
New Hard Disk: Since I have these nifty hot swap bays, I debate purchasing a hard disk solely to carry the stuff needed to score a big fat 3DMark score.
Arctic Silver on the Northbridge
I don't know if this is a requirement or not, but I accidently squeezed a little too much out of the tube when installing my brother's new mobo, so I had to put it to use. This was an easy mod. The fan is held onto the KD-7 with some little plastic gizmos that push through the hole and then stick out barbs. Use a needle nose pliers to squeeze 'em shut and you can remove the fan without damaging anything. When I got the fan off I saw what had been rumored on the overclocking forums: Abit puts absolutely no thermal compound on these things. Adding AS couldn't possibly hurt and might do a lot of good. Apply Arctic Silver the way their site says to, then reinsert the little pins to remount the fan. Voila! The forum posts I've been reading claim this can be good for a few more MHz of FSB stability.
Just after dabbing on the Arctic Silver but before spreading it...
Overclock Baby Steps...
First thing was getting the mobo running. This proved to be harder than it should have been. When I first fired up the KD7, it would run for 2 seconds and then shut itself off. Support from Abit is abysmal and I was doing this on a Sunday to boot. In any event, after hours of fooling around, I finally took the board out of my case, tore it completely down, took the water block off, stuck on my trusty Zalman, and tried again. Low and behold, it worked!
We'll probably never know why it failed, but this seems to be the nature of computing these days. Things are so complex its much more art than science. Once I had verified everything was okay, I decided to try a little overclocking. Since all I had was my old Mushkin 512MB PC2100 DDR RAM sticks, I wasn't going to get far anyway. They say burning in really matters for these systems, so I'm going to just start out with some simple baby steps. Meanwhile, I have ordered some fire-breathing Geil PC3200 RAM to pick up the pace later.
When you start overclocking you need some way to measure your progress. A set of benchmarks, if you will. I use the SiSoft Sandra series together with 3DMark2001. Take a baseline of your system. Here is a set of runs I made using these benchmarks:
As you can see, I still don't have things running as well as my best 3DMark on the old K7S5A board, but this is because that run was with my GeForce 3 overclocked and I haven't gotten there yet on the new system.
So what did I do?
After establishing the baseline, I started to ramp up the FSB speed, keeping a CPU multiplier that would leave the CPU running at about its stock 2 GHz speed. This is how you're supposed to overclock these AMD systems. By default, Intel's have much higher memory bandwidth, especially the RDRAM systems, so AMD's are starved for access to their memory.
From a stock 133 (heck, some run at 100), I got the FSB up to 150. Not great, but not too bad either considering my crappy DDR memory. For comparison, the "serious" overclockers run 200 and above, but with questionable day-to-day stability. I think 180 is more common on a day-to-day machine. On these boards, running at too high FSB results in a sort of hard disk corruption, noted on several of my tests. Basically, the system will be unable to find key Windows system files while booting. Don't spend long here or you'll be reinstalling Windows!
I tried to tweak up the CPU, but it wouldn't run much higher than stock without triggering random reboots. I'll revisit this issue again when the system is "burned in" because the 2400+ chip should be capable of much more.
You can also see on some of my failed attempts that I attempted to create more stability by upping voltages. This is a dangerous business because it can drastically shorten component lives, but hey, who wants to be running the same hardware years later anyway? Unfortunately, adding voltage didn't seem to accomplish much. Again, this is an area I need to play with again later.
My next step was to go in search of newer nVidia drivers for my GeForce 3. nVidia constantly improves their drivers, and as you can see, the switch in drivers boosted my performance almost as much as some of the overclocking! While on this same vein, I downloaded the latest Via 4-in-1 drivers (these are motherboard drivers) to see if they could make a difference.
OK, at this stage, the system is much faster on the SiSoft benchmarks than the old K7S5A, and even betters the default new board in all the benchmarks. What's next? Having done the basic system overclock (at least until I get some more memory, more time, and things have burned in), I am turning my attention to the GeForce 3 card.
Tweaking the graphics card requires a special utility. I use RivaTuner, which is a great tool for tweaking nVidia-chipped graphics cards. There are others available for ATI cards. And here's what I accomplished:
Now we're cooking with fire! First, I recalled needing to install the VIA 4-in-1 drivers. These include a new AGP driver for the graphics card. Wow! Performance rocketed ahead on the 3DMark from 6,463 to 8,328. People: make sure you've got the latest version of every driver on your system!
Next, I used Riva Tuner to start cranking up the clock speeds on the core and RAM of the GeForce 3 card. I was able to get to 240/515 MHz. Any more on either and my system would reboot or hang up in the benchmarks. We've brought the system along all the way to 9,248 for a 54% gain over the basic KD7 board and a 39% gain over the old K7S5A system. Not too shabby!
All material © 2001-2006, Robert W. Warfield.