View Full Version : First stupid overclocking question of many

01-31-2005, 12:32 PM
I have an Abit IC-7 max2, 2.8e 800, OCZ plat rev2 and I took my first stab at turning up the FSB last night, no joy.

at 210 FSB I got a Bad System Config error and at 220 I got a checksum error.

I noticed that the AGP/PCI frequencies went up with the FSB and from reading I seem to understand that you want to avoid this. So I need to "unlock" that ratio to allow the FSB to climb and the AGP/PCI to stay at 66/33?

01-31-2005, 12:44 PM
The proper word is really locking! There is an option in your bios to simply fix agp/pci at 66/33, no more no less. Usually unlocked overclocks can only go to 217-222 mhz before something in the pci bus goes crazy.

01-31-2005, 05:28 PM
Thank you for pointing me in the right direction! I was leary of touching the CPU:AGP:PCI line in BIOS without really having any hint that that was what I needed to do.

Solving that problem revealed another, of course. Using all 2.8 volts XP wasn't stable. I decided to try 2.5 3 3 5 instead of stock 2.5 2 2 5 and now the machine runs smoothly at FSB 220.

Is voltage what it takes to get to the lower latencies?

01-31-2005, 05:57 PM
Am always confused by this I have a Gigabyte GA V7axp mobo and just wondered is there s/ware that allows any mobo to lock the Agp/pci freq?

02-01-2005, 05:50 AM
Samsung Tccd chips cant do high fsb with tRCD at 2, they usually freak out before 220mhz and sometimes even before 210mhz. 2.5-3-3-8 is usually tccds best friend, you shouldnt need more ddrvdd than that, and most probably 2.8v will suffice up to 250mhz or more because they aren't power hungry.
Only winbond ch/bh/5/6 usually keep trcd at 2 with lots of voltage at high fsb.

IIRC, that gigabyte has a via kt400 without working locks. I guess the only via who has them is kt880 for socket A.

02-01-2005, 06:32 AM

02-01-2005, 08:28 AM
I'm no expert but I have my P4 2.4 northwood system o/c to 3.02Ghz with an FSB increase from 133 to 167 (just wish I had a 200FSB chip). I know a new PSU and new faster RAM helped tremendously (Antec Trueblue 480W and Geil Performance PC3200 2-3-3-6 1gb Dual channel). I already had a good ehatsink and fan to keep it cool. Before the new items I could only manage 2.75Ghz stable.

I believe only certain mobo have PCI/AGP locking on them. I've had 3 gigabyte boards in my time and none of them have had it on. These were all pentium based boards so I can't vouch for any differences with AMD.

I think when you push the FSB up you also effect the RAM as well so with any PCs there are also bottlenecks IMHO.

Good luck with it.

02-01-2005, 09:41 AM
Thank you Bela, I take your comment as a tacit suggestion I switch to 2.5-3-3-8 from -5.

I am using MetaBench to test changes, is this satisfactory? Current score 3290.

Perfect, 250 FSB is what I was told to expect from the memory at most at 2.8v and that I'd have to relax the timings to get there. You are exactly correct, 200 FSB runs fine stock, nothing else does.

Absolutely no difference in frame rates in Black Death with a 9800pro. With an 11.7% increase in a synthetic benchmark score, no less, on a 10% increase in FSB/processor speed. Should I go back to 200 FSB or have I picked up performance I won't notice until the sky is full of planes and gunfire?

02-01-2005, 12:15 PM
"I switch to 2.5-3-3-8 from -5"
5 or 8 gives a very small difference, probably at low fsbs 5 is faster, but at higher ones you might need to set 8. Still, I doubt you'll find any differece in performance.

"I am using MetaBench to test changes, is this satisfactory? Current score 3290."
Heh, I wish I could tell you, but I don't now either that program or what exact values to expect in intel systems. Currently I'm in the other side of the force http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif.

"Perfect, 250 FSB is what I was told to expect from the memory at most at 2.8v and that I'd have to relax the timings to get there."

Tccd chips are rated for 250mhz 3-4-4-7 IIRC, but they almost always do 250mhz at 2.5-3-3-8, hence my recomendation above, usually the only need very relaxed setting near 300mhz on amd systems, but every part is unique...
On the side of ddrvdd, usually 2.8v can give you lots of headroom with those chips (altough it depends on their rev. and brainpower pcb rev. too), tccd can usually scale up to 3, 3.1v, but most times for what you see around it's very possible reach 250mhz stable with such "low" voltage. I don't wan't to give you false hopes that you can surelly do 250 2.5-3-3-8 with only 2.8v, but odds are good.
Remember that up to there, there are other much more important variables as cpu batch, temps you are running, mobo capabilities, PAT settings, vagp, etc.

Let me look for a good starters link... aha, found it.

http://www.pcholic.net/overclockingIC7.htm , take special note on gat settings, I guess your mobo has them as the ic7-max3. Good luck, if you ask around for specific stuff, you'll surelly find a lot of info from experienced intel users around here.

02-01-2005, 01:54 PM
WOW, thank you!

I am curious to know if anyone has experience as to whether I am getting any benefit for gameplay with this overclock. While my frame rates haven't changed at all, am I getting the ability to handle more objects in game?

I plan on upgrading to 16 pixel pipes at some point, so this extra muscle will be needed in the next 6 months or so.

02-01-2005, 02:20 PM
Sunflower, if you go up on the clock or tighten up your timings and you get zippo improvement, it means you are starting to get errors. It can take hundreds to thousands of read/write errors before Cousin Billy's operating system will tell you a thing about it. By the time you get one of those IL-2.exe is closing to prevent brain damage type messages, you are way down the road on errors. Not only are you pushing the frying limits by going that far, you invite something called RAM burn in where it will slowly be less able to keep those clcoks and timings over time. Always find your highest truly stable all the time speed and back off 20% of the overclock for stability. So, if you go from 200 to 250 on the front side buss, that's a 50 overclock, so 20% of 50 is 10... drop it back to 240 and it will run like that fine.

I have a cheap and easy mod that will help you manage your hotplate (Prescott chip)...

You buy one of those PCI slot fans and take the metal grill part of it off. You tape off the top side of the exhaust so it only blows air out the back portion equal toi the distance your motherboard sits away from the backing plate. You use some silicon glue or the thin kind of the double sided tape and put the exhaust of the fan up against the motherboard and like elfin majic, it will cool your motherboard as well as if you cut a hole in the right side of the case and mounted a fan with less noise and certainly less mess!

This will help cool your motherboard. If the motherboard is cooler, your RAM will be cooler and it is very, very sensitive to heat. Coller RAM clocks farther and stays stable at higher clocks. Right now, with my PC in Turbo RAM timing mode on my ABIT IC7-MAX3 mommaboard, my cheapy Corsair Value select does a front side buss speed of 220 no problems at all.

02-01-2005, 08:47 PM
Bela's pointing me to lock the PCI/AGP and confirming that relaxing the timings was correct has me running cool and stable at 220 FSB, no crashes at all.

The computer is clearly running faster, I've used several other benchmarks now and they all show the improvement, but none of it results in better framerates in the game. I assume that this is because the 9800pro is already pedalling as fast as it can.

I do wonder, though, whether or not I've picked up the ability to handle more objects and action. My understanding is that these things put comparatively more load on the CPU than on the video card.

Would using QMB at various FSB's and differing amounts of AI fighting it out reliably tell me I am getting a benefit?

02-01-2005, 10:22 PM
Yes, you've picked up that ability and so many people discount it until they've flown their first night mission in a thunderstorm with lots of AI bombers and ships and rocket trucks and AAA and tanks...

Yes, your 9800 Pro is saying... whoah now!... wait a minute here... huff, puff!

Also, run the Black death track and see if you haven't picked up like 1 frame at the bottom end where it counts.

02-02-2005, 01:38 AM
No improvement in minimum fps.

I turned the heat down on the video card and the overclock showed up immediately. I'm running perfect at 12x9 and that makes the CPU irrelevent at some point below a stock 2.8e 800. The oc would allow, say, for going from excellent 10x7 at 36 fps to excellent 12x9 at 36 fps. Perfect 12x9 runs 23 at 200 FSB or 220 FSB.