OCing Q9550 on Gigabyte P35-DS3L - problems and ?s

Colonel Sanders

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Previously I was running an E6750 @ ~3.54ghz (see sig, since I haven't updated it yet). That was a FSB setting of about 444. Now I just bought a Q9550 CPU from a member here and am trying to get a decent OC out of it.

Previous user of this Q9550 said he was doing 3.8ghz (which is around 447mhz FSB @ 1.25v). I figured I would start a little under there and work my way up. Much to my dismay the highest FSB I can use (and get into Windows and run Prime) is only 400 (3.40ghz).

I have it set at the stock voltages all around except +0.3v on the DDR2 to achieve the rated 2.1v of my RAM, and the CPU is at its VID of 1.2375.

Also I have the RAM set to super stable 1:1 and lax timings just to take it out of the equation for now.

I have tried upping the vcore manually which made absolutely no change. I can get a post beep and bios showing 3.80ghz (and higher) but it immediately locks up, shots down, then reboots back to default bios settings. It does this regardless of vcore (I tried up to 1.31v) and FSB voltage (which I tried up to the max the board allows of +0.3v).

Anyone have any tips here? Why can't I do any decent FSB with this quad core when my Duo could hit almost 450 without any problems?

edit: Also just to add, with my Zalman CNPS9500 at stock 1.2375 vcore on the Q9550 my temps hit at most ~58c on the first core running Prime95, the rest are a few c lower. Programs like HWmonitor show overall core temp not exceeding 47c.

edit2: Google is my friend. Apparently the P35-DS3L is fantastic for overclocking Duo cores but not Quad cores, and just like my experience, most people can't get it much over 400-415fsb.
 
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Previously I was running an E6750 @ ~3.54ghz (see sig, since I haven't updated it yet). That was a FSB setting of about 444. Now I just bought a Q9550 CPU from a member here and am trying to get a decent OC out of it.

Previous user of this Q9550 said he was doing 3.8ghz (which is around 447mhz FSB @ 1.25v). I figured I would start a little under there and work my way up. Much to my dismay the highest FSB I can use (and get into Windows and run Prime) is only 400 (3.40ghz).

I have it set at the stock voltages all around except +0.3v on the DDR2 to achieve the rated 2.1v of my RAM, and the CPU is at its VID of 1.2375.

Also I have the RAM set to super stable 1:1 and lax timings just to take it out of the equation for now.

I have tried upping the vcore manually which made absolutely no change. I can get a post beep and bios showing 3.80ghz (and higher) but it immediately locks up, shots down, then reboots back to default bios settings. It does this regardless of vcore (I tried up to 1.31v) and FSB voltage (which I tried up to the max the board allows of +0.3v).

Anyone have any tips here? Why can't I do any decent FSB with this quad core when my Duo could hit almost 450 without any problems?

edit: Also just to add, with my Zalman CNPS9500 at stock 1.2375 vcore on the Q9550 my temps hit at most ~58c on the first core running Prime95, the rest are a few c lower. Programs like HWmonitor show overall core temp not exceeding 47c.

edit2: Google is my friend. Apparently the P35-DS3L is fantastic for overclocking Duo cores but not Quad cores, and just like my experience, most people can't get it much over 400-415fsb.

That would be my old CPU:) That quad should easily hit 3.8 ghz as I had it at that spec 100% stable whenever my pc was on. I had it to 4.0 ghz for benchmarks and never exceeded 1.30v. The other interesting fact is my Q9550 reported a VID of 1.1250v via coretemp program. Are you looking at CPUZ voltage, as that doesn't mean VID?

Honestly, your motherboard is probably holding you back being that is a p35 board if that is what your using in your signature. I was using a evga 790i ultra which had a pretty decent FSB.

Here is my original post when I bought this quad that mentions my VID and OC of it, and that was my first OC of this chip.

http://hardforum.com/showthread.php?t=1450567&highlight=Q9550

From my experience, a quad typically doesn't OC at the same FSB as a dual core on the FSB. I've always got lower FSB on a quad when I've used a dual core on the same motherboard. This has been true for me with the following cpu chips I've had the past 4 years or so with socket 775 (E6600,Q6600,E7300,Q8200,Q9550).

With my 790i board, I had cpu voltage at 1.25v, FSB voltage at 1.4v, DDR3 ram 1333mhz at stock voltage and timing. Other than that, I don't recall exactly what I had all the settings to reach 3.8ghz being that I haven't used that rig for at least a month since I've built my I7 930. If you get a newer board, that chip should OC nicely.
 
Whatever settings you used for your dual will be different with your quad. I learned that the recently oc'n my q9550. I've been messing more with the GTL voltage settings for my northbridge and GTL buffer strength. My board can do 500fsb with my dual without breaking a sweat. I'm at 440 stable. I'm aiming for 500fsb but it's not looking too good
 
Increase the FSB voltage. (This affects the GTL voltage on the FSB). Use smallest steps available and it make take a couple of bumps before you see improvement. Test and see. You can go too far and while the OC will look good you will get random lockups during operation if you go too far so you need to go slow and test by using. Once you see (if you see) increase helps OC just maybe try one more bump. More is not always better with this setting. There is a narrow range where more voltage helps overcome the load of the quad on the buss but it just takes a bit more to create invalid logic values on the buss and it all goes to crap.

Keep in mind you have the "L" board which is the low cost "light" version with no cooling on the CPU voltage regulation mosfets. I would not recommend a balls to the wall OC on that board unless you have a fan blow air directly on the components around the CPU socket. Gigabyte gives that board the full featured OCing bios but the components on the board and especially the cooling of those components are not as beefy as the non-light version.
 
I know everbody's mileage may vary, but I never had great success overclocking C2Q's on P35 based board. Used to have a DFI P35 T2R and like you, a P35-DS3L, and never could get anywhere north of 400 FSB range, even though I could easily hit the 500+ mark with C2D's. I even upgarded the board cooling by adding heatsinks to the mosfets and things wouldn't budge regardless of the voltages and other tweaks applied.
 
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I'm sure you can find a cheap but good P45 Express chipset mobo surely?

I have an E0 Q9550 and just by upping the PLL and VTT with a shade bump on the vcore (1.31) I am at 4GHz with 471x8.5 and that's on 8GB of RAM (2.1v @ 1:1).

Board is an EP45-Ud3P btw.
 
I have the exact same board.
I had the exact same problem when I upgraded to a quad.
Update your bios.

/thread :)
 
I was able to do 3.6ghz on that board before it died, after a years use. I have since replaced that board with the ud3p. All I did was increase the vcore to 1.4 and I was good to go.

Edit: This thread has inspired me to give my oc another go round. I enabled llc and can get to 3.6 ghz at 1.35vcore, which lowers temps a lot. I have gotten 3.8ghz to be stable during gaming, but fails occt cpu after 15 mins and linpack after about 4 seconds.
 
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Well, whatever Sander's issues were, hopefully I don't inherit them :). I bought the chip yesterday, so hopefully my ep45-ud3p takes to it. I have a mcr320 and a swiftech GTZ, and have no intentions of being gentle.
I finally get to retire my trusty E8500. Its lived a long hard life, but its still kicking!
 
Gigabyte EP45-UD3P are better for overclocking Quads. I'm stuck at 8.5x450 on my DFI UT P45. It's rock solid at 1.216 volts.
 
yes i got a gigabyte p45-ud3p also i oc my q9550 to 4ghz. w/1.25v with llc enebled. this is a great board and there hard to fine anymore.
 
llc enabled? Everywhere I read that = death for 45nm chips. I guess your vcore is low enough not to be an issue.
 
I was talking to valtopps :p

You can't kill Q6600's...those things were tough. I had buddies pumping upwards of 1.6v into them with good cooling. I still miss my E6600 dual core....I never had such an easy time overclocking a chip :) Sure, my E8500 clocked higher...but it was very very fussy.

Anyways, I got a new toy to play with now. I wish FedEx would hurry the hell up!
 
CPU has arrived and is installed. VID is actually 1.2375, which came as a minor shock...even though it is clearly posted in the first post (must have missed it). However, its running at 3.4Ghz without a voltage adjustment, and in my eyes that's a good sign. Lets see how far it will go.
 
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