Issues OC'ing a 2800+ (PLEASE READ)

[Caviman2201]

so that's the verdict, huh... the PCI bus... is it a componet of the PCI bus or the chipset itself? Someone please tell me why I can't go higher than 174...

you should know, before I upgraded the memory and processor, I was running 1G of DDR266 and a 2400+ at 145 stable.. a 12MHz overclock... why would my PCI now, the same PCI only accept a 8Mhz overclock? I haven't added any new componets except a Sony DVD-ROM drive...

 

[Caviman2201]

c'mon where are the experts? you guys usually have a ton of ideas/solutions for me... where are you guys?

 

[Caviman2201]

Ok... just got an error while running Aquamark3... an exception fault @ 174MHz... c'mon guys... is my memory dead?

 

[Fleck]

What are your CAS latencies?

My PC3200 stick can do over 210 but even at 200, it couldn't do the stock settings (6-3-3-2.5) and had to be set at 8-4-4-2.5 for 200 and 205 and 9-5-5 for 210.

 

[OC Detective]

your voltage rails suggest that is not the problem and we cant eliminate memory as a problem unless you do memtest or use RAM different from what you currently have - that said if you are using JUST the crucial DDR400 it really should be OK. I still cant see the PCI being a problem at 35. (My A7V333 is at 36 at the moment and you previously have had yours at 36.25). The other possibilities are the temperature read-out is inaccurate - what heat sink fan combination are you using? The cpu may just has reached its limits for the system set up you have. Other possibility is some set up in your bios is limiting your overclock.

 

[Caviman2201]

ok... here's some info i found out... maybe it'll take the investigation further...

1) the chipset i have, the KT400 (as opposed the the KT400A) supports only PC2700 RAM when running a 333MHz FSB CPU.

---In my BIOS, I have the memory bus speed set manually at 166MHz, so when I overclock, the FSB will be syncronous with the memory bus. I'm not sure, but I wouldn't think this rule would apply so long as I'm running the DDR400 RAM at DDR333 speeds.

2) I ran Memtest86 for 2 passes on the DDR400... no probs no errors. Went back to Aquamark3 and still got an exception at 174MHz so I dropped it back to 172MHz and my scores dropped dramatically.

3) I swapped out the DDR400 for a pair of 256M DDR333's I had and tried OC'ing them to 174MHz... didn't work... exception fault in Aquamark3.

--- after all this, I'm guessing it's not the RAM... I can't get above 172-ish without exception faults with either RAM and the DDR400 was checked clean by Memtest86.

and Fleck, my CAS latencies are stock... i have the RAM timings set as "by SPD" in the BIOS... i figured since I was running DDR400 @ DDR344 speeds, I didn't need to worry about it.

 

[Fleck]

Ha-ha-ha! My ram was so fukkey it didn't like *ANYTHING* until I lowered the latencies...

It passes any memtest86 test with flying colors albeit unstable, by the way.

 

[OC Detective]

OK then we can rule out RAM, PCI and voltage being an issue. I would still like to know your heat sink fan combination and thermal paste you are using. Also a careful check through the bios setup to ensure there are no possible blocks to overclocking there.
Oh and I just checked the manual for your mobo and according to that you CAN up the vcore its in the submenu for Frequency/Voltage control. I would recommend you adjust that upwards as your voltage rails are good.
One final thing make sure the jumper JCLK1 is set correctly for 166FSB but I assume that is.

 

[Caviman2201]

Which manual did you look at because I have the paperback manual right here in front of me and it says nothing of voltages...

the setup I'm using is an Ultra TMD Socket A up to 3200+ with the generic heat sink compound that came with it... I don't think the thermometer is defective...

and I'm not really sure how to go about looking through the BIOS to find any "blocks"

and Fleck... I have no idea how to tweak latencies or timings on my RAM...

 

[Caviman2201]

oh ok... I see what manual you looked at... at the top of the manual, it says that you can change vCore and CPU/PCI clock, but if you scroll down to the bottom, page 30... it shows an exact picture of that submenu...

It looks the same on my comp... only the CPU clock is there, no voltage settings

 

[barton2500]

I suggest you get a NF2 board because it has an AGP/ PCI lock. I've an unlocked barton2500 on A7V8X-X and I can't bump up the FSB on that because of the PCI clock issue. But on my thorton2400 on A7N8X I am able to raise the FSB.

Lesson: locked processors with no PCI lock = no overclock

 

[Caviman2201]

now another odd thing has started... about every 10-15 seconds, it's like my computer skips a beat... if I'm typing a sentance, it will freeze for less than a second and then jump back to place... games do the same thing... freeze up for less than a second and then jump back... it's barely visible... but it's doing it constantly... I'm going to take everything back to stock... FSB and video card and see if it continues...

**** OK... i set everything back to stock speeds... FSB and video card are running stock and the problem went away... I think my motherboard just DOES NOT LIKE OVERCLOCKING at ALL!****

what do you guys think?

 

[Hawker-rider]

it sounds to that you just need to take sme time and find the bottleneck for your system.

UNSERclock most of the system, videocard etc, so that that won't be an issue, plug in the DDR400 ram only and see how far you can get the processor to go. . find the page that you can change the timings of the ram too, and loosen that up just a bit.

Just find the CPU limit first, when the pc will have problems booting...that's our first number, go back to a good and stable CPU setting, then tighten the timings on the ram slowly, after every step do plenty of testing.

A far as memtest goes, just let it run overnight, or while you go to the grocerystore, so it can do a bunch of complete passes, and then check for errors.

i had prime95 fail on me after a bunch of passes, and ran memtes tovernight, after the 6th full-test it started showing a few errors in the last pass, tweaked that and wham! passed all tests.

Find the culprit then we'll talk more.

 

[Caviman2201]

the thing is with the RAM timings... I dont' know the first thing about it... I have no idea what all the 7T and 2-3-3-5 stuff means... (those aren't my timings, i just picked those #'s out of a hat)

 

[Caviman2201]

Everything is downclocked to specs right now, however, and I'm still getting that annoying skip a beat thing every few seconds... it's about every 30 seconds it will do it... it just seems to.. all i can describe is skip a beat... it's annoying as hell

 

[OC Detective]

I think the fact that you have limited overclocking features on your mobo is the problem here. Oh and temperature measurements on the cpu are notoriously inaccurate especially if not on die. You seem to be using a low grade HSF setup and I think an improved HSF combination would help here.

 

[Caviman2201]

heh... ok... you're gonna laugh... I figured out what was causing the "skip a beat" problem... whenever my un-named P2P downloading software hit a good server, whatever else I was doing would jump when it wrote the downloaded data to my HDD... thats why it was only for a second and thats why it was intermittant... when it hit a decent server, it would do it less often than when it hit a really fast server... hahaha... once I'm finished downloading this file, I'll let you know if the skip returns but I doubt it will... I killed the P2P software and the skip went away...turned it back on and the skip came back...

about what you were saying before though... you basically think that my Mobo is just not meant for overclocking and that I should basically hang it up until i get an nForce2?

 

[Artisan]

I think your 3d apps are crashing because the agp bus is at 70 and it is throwing off your video card. (They can be pretty sensitive) Couple this with an oc'ed card and its tough to get past.

Anyone know when the dividers kick in for this board?

Its possible that overclocking the fsb more, to the right point that gets the agp bus back at 66, could solve your problems. That's if a new divider exists and you can make it high enough to reach it.

You could try testing stability with prime 95 as you work your way up and check and see if the pci/agp bus gets back to normal at some point. That would probobly be about it for your oc though, if you havn't already reached the highest divider.

If you have, do anything, return any parts you can, sell the slower memory and your current mobo ect... and get an nforce 2 chipset mobo.

 

[Caviman2201]

yeah... my mobo only supports the 1/5 divider so at 175MHz, the AGP is at 70MHz... I'm leaving my parts at stock for now... I'm going to probably get the ASUS A7N8X-E Deluxe in the next month or so... but I'm keeping this one at stock clocks to keep from damaging my vid card or any of my PCI devices until then.

 

[Caviman2201]

Ok, well I guess I've learned quite a bit in my little spat with overclocking...

Lesson Learned: you get what you paid for... don't expect to be able to overclock and tune a cheap motherboard too much just as you wouldn't expect to be able to soup up a Kia... buy a top-end mobo and you'll have the options...

thanks for all the help guys... I appreciate it