At the moment, I'm trying to overclock my E6300 with my GA-945P-S3 motherboard.
The problem I'm having is I can't get stable overclocks without overclocking the PCI-E bus. Like serious overclocking. To get past 2.4GHz I have to push the PCI-E bus frequency above 110MHz, and from what I've heard this doesn't seem right.
I've tried changing Vcore, FSB over voltage, DIMM over voltage and all that jazz, to no effect. It only POSTs above a 300MHz CPU Host Frequency if I overclock the PCI-E bus in line with the host frequency overclock (e.g. 100 -> 110 -> 115 etc).
My setup:
Processor: E6300 (1.86GHz)
Motherboard: GA-945P-S3
RAM: Corsair DDR2 XMS2 (667MHz, 5-5-5-12 timings)
Cooler on processor: Thermaltake Big Typhoon 120VX
Case: Antec Nine Hundred (2 x 120mm intake, 120mm side intake, 120mm rear exhast, 200mm top exhast)
PSU: Corsair HX620W
GPU: MSI NX 8800GT (factory overclocked)
Grease: Arctic Silver 5
HDD: 2 x 250gb
Theoretically I should have plenty of cooling, so I don't think that's the problem. Overclocking the PCI-E bus frequency worries me, and not being able to overclock without it worries me even more. Unfortunately, google hasn't been much help.
Message edited by ryan_au on 04-24-2008 at 01:14:51 AM
That is a interesting problem. According to MSI's website, it's safe to go up to 120Mhz on the PCI-E frequency, and I'm sure the 8800GT can handle that.
Anyways, by stable, do you mean at least 8hours stable in Prime95 small FFT's and 12hours stable Prime95 blend? Longer the better.
Try flashing to the latest bios.
--------------- "Nvidia, the Way It's Meant to be PAID Played! - Corrado
*Lesbian Lover Club* - founder Assman
You should never overclock pcie so long as you can help it. It's a bad idea, and basically comes with no performance benefits. Graphics cards are expensive, don't risk burning it out.
Any half decent overclocking board should let you lock pcie frequency.
Dagger, I don't think you understand my predicament.
I _cannot_ get stable overclocks past 300MHz cpu host frequency without overclocking the PCI-E bus to 3 x cpu host frequency + 1.
At the moment I am running a 347MHz cpu host frequency and a 117MHz PCI-E bus frequency. If I drop the PCI-E bus frequency any lower, I can't get a stable overclock. I'm thinking it has something to do with my motherboard.
Evilonigir i, could you please share your settings?
You should never overclock pcie so long as you can help it. It's a bad idea, and basically comes with no performance benefits. Graphics cards are expensive, don't risk burning it out.
Any half decent overclocking board should let you lock pcie frequency.
Too true, but didn't you read what the OP said? He said without OCing the PCI-E frequency, he can not get his system stable. I'm thinking maybe it's some fsb hole...
--------------- "Nvidia, the Way It's Meant to be PAID Played! - Corrado
*Lesbian Lover Club* - founder Assman
Ok erm don't want to dumb down the the help, i know you've said you've tried all that jazz, but if you've left your RAM on Auto it'll i'm guessing have defaulted to 266 with lower than spec Timings so just increasing the vDimm won't work.
Could be a pointless hypothesis, however it's out there now... <-- look at me with my big words - lol
*Edit* I understand this doesn't explain your PCI-E temp fix, but as far as my depth goes it's one of those...do not fiddle with or you'll break summit thingers.
Message edited by closed_deal on 04-24-2008 at 03:11:50 AM
Ok that could also be the problem your specs say you've got 667Mhz RAM now to get 868Mhz is a ruddy good overclock on the RAM and is most likely the limit.
I'd suggest changing your multiplier further and trying again. If it still doesn't work i'm befuddled.
Message edited by closed_deal on 04-24-2008 at 03:18:08 AM
I've pushed the RAM past 900MHz in previous overclocks (higher PCI-E frequencies) and it seems to be stable.
I'll drop the memory multiplier back to 2.0 and the RAM will be running at ~700MHz, so that should rule out a RAM overclock limit. As roadrunner said earlier, maybe that will help lock the PCI-E frequency (even though that doesn't seem to be the issue).
Maybe your ram dont like to OC that much. Run 1:1 and how high of a vcore have you tried. If you have a good cooler start at 1.5 and work down til its unstable.
If it dont work I think 115PCIe is ok but I wouldnt go higher. Maybe you got a bum chip.
Is that old stepping or is it M0 stepping. How high have you got it to run stable? What is the multi on that
Righto, this is the first problem I've heard in just over two years at overclocking that involves the PCI-E and increasing it to get better stability at fairly low clocks. It'll be interesting to find out what fixes this.
^^^^I agree with the 115Mhz max PCI-E
Message edited by closed_deal on 04-24-2008 at 03:24:18 AM
Looks like you have B2 stepping and a 7x multi. Ouch! You be lucky if you get over 2.4.
You would be better off with a e21xx series as they are mo and have 8,9,10, multis. Or the e2200 at 11x multi is a bargain right now also. Also the e4700 that is new has a 13x multi. Now I'd like to see what that baby can do!
7x multi, old stepping, and old chipset is gonna hold you back.
Message edited by roadrunner197069 on 04-24-2008 at 03:27:28 AM
Really? I know a lad with an e6300 running at 3.0GHz with stock cooling.
Anyhow, I dropped the PCI-E bus frequency back to 100MHz, and so I can only get stable overclocks at 290MHz cpu host frequency. That means my RAM is running at 590MHz on a 2.0 memory multiplier setting.
3.0 would need 428FSB thats pretty insane for your chipset. You need to put Vcore at 1.5 to see what she can do. Yor Vcore is definately holding you back. I need 1.2875 for 300FSB on my e2180 and on the other computer I got with e2180 it needs 1.4 for 3.0 same ram, same mobo.
Your lad probably had a P35 chipset or x38 chipset.
If you dont up VCORE your not gonna get any more.
When you want to OC "BIG" it is always a good idea to get a motherboard that runs a higher FSB then your CPU. 1066FSB mobo with a 1066FSB CPU aint gonna pull impressive numbers.
Message edited by roadrunner197069 on 04-24-2008 at 04:06:01 AM
It says right on the box it can go 1.5, just watch the temps. 1.5 should get you a few more clicks but be sure once you find your FSB limit to lower the vcore to the lowest voltage it will run stable.
Unfortunately, upping the Vcore to those voltages does absolutely nothing. I tried it just then. The _only_ thing at the moment allowing me to overclock is upping the PCI-E bus = (cpu host frequency / 3) - 1 (or 2)
