Hey fellas. I'm a bit new to the C2D overclocking scene and I seem to run into a FSB Wall with my E6550 C2D Processor. Currently I can find 100% stability at 416FSB on 7x multiplier which brings the cpu to 2.912GHZ from 2.33GHZ default. Vcore is currently set at default 1.35v, DDR voltage at 2.2v. MCH and CPU VTT at default as well (1.25/1.2).

I have tried upping the Vcore to 1.47 max, upping the MCH to 1.5x, CPU VTT to 1.49. Memory was and still is always at 2.2v max. Memory timings 5-5-5-15 and I have disabled C1E and EIST features in bios.

I also tried lowering the multiplier from 7x to 6x and I still can't seem to break 418FSB no matter how hard I try.

Are there any suggestions anyone would recommend me to try next?

System specs:

E6550 C2D
Abit IP35-Pro
Tuniq Tower 120
OCZ 2x2GB SLI-Ready edition PC-6400
Thermaltake PurePower 600w
BFG 8800GTS G92 512MB

not many boards can go past 1600mhz fsb. with ddr 6400 you wouldn't have the bandwidth to utilize more then a 1600mhz fsb. so yes you've hit a wall. the only way to continue overclocking is to get your self an extreme edition cpu.

I don't see how that is true. I've read other people's e6550 overclocks and most are able to push past 430fsb just fine.

http://xtreview.com/review216.htm In this review, three e6550 were able to be pushed as fast as 480FSB clock and on the screenshot, the board's FSB is well past 1600mhz fsb.

As for my earlier motherboard comment I stand corrected on it. But they are using much faster ram then you are. ddr2 1142 which in dual channel gives them about 2284mhz for the fsb. where your ddr2 800 is only giving you 1600mhz

my memory won't run at DDR-1600, yes, however it doesn't work that way. My current memory speed is at PC-998 overclocked with a 1:1.2 FSB divider (416FSB * 1.2 = 499. 499 * 2 = 998) So my memory is ok at PC-998. I can set my FSB divider to 1:1 and thus pushing 430mhz FSB will be fine for my memory but my system is not stable past 416fsb.

So it is not the memory that is the problem. I think it may be the CPU but i would like more confirmation from other experts on this situation. People have been using the IP35-pro for much higher than 416FSB overclocking lol.

yes i udnerstand that but my point is that their is little reason to have a cpu fsb higher then your memory speed. if your memory's maximum is 800mhz. 1600mhz in dual channel. then any fsb speeds higher then that will not produce a performance gain. the extra cycles the pc goes through waiting for the memory to catch up will go to waste. So your system is pretty much clocked as fast as it will go without upgrading your ram.

right now your clock is set to 416. 416mhz x 4=1664mhz fsb. your memory is ddr2 800mhz in dual channel it's 1600mhz of bandwidth. system is 1 to 1 with the memory which is ideal

my ram is not bad however.

OCZ SLI-Ready Edition 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory

http://www.newegg.com/Product/Prod [...] 6820227269

that is my memory. OCZ website is down btw so sorry I can't get a direct link to official specs from their own site

Your ram is great but still only rated at ddr2 800. if you want to push past the 1600mhz barrier you'll have to OC the memory. again if you research the article yor posted earlier they are using much faster memory.

I have the E6550 and I am running it at 3.4Ghz, at a FSB of 485.

I think it's probably your motherboard. Because 416 seems kind of low. I think my voltage is just a little higher than stock for the processor, so you shouldn't need to much voltage on the processor to get higher clocks.

Your memory at that voltage should be able to get higher than 832.... but then again your motherboard should also be able to handle it.

Honestly, I don't know what's happening. Maybe your processor just isn't up to the higher front side buses. Sometimes that happens.

I guess I would just suggest increasing the voltage with everything just a little bit, and see if that helps.

yeah that is an impressive overclock. are you running air cooling? if you don't mind what spec is your computer.

Btw, I highly doubt it is my motherboard. The Abit IP35-pro has been known to reach high FSB overclocks. Just look at the previous review link I posted

I'm really thinking I got an unlucky lottery pick on the CPU. Not that I really had the chance or knowledge I picked this CPU up long time ago.

Motherboard: Gigabyte GA-P35-DS3R
CPU: E6550@3.4Ghz cooled by Tuniq Tower
Ram: GeIL 2GB DDR2 800 (the orange ones)
Hard Drives: 74Gb Raptor 500Gb Western Digital Caviar
Video Card: Sapphire X1950pro(256mb)
PSU: Rosewill RP550
Case: Antec 900

I don't think I left anything out...

Anyway, yeah my Tuniq Tower does a great job. About 32C idle and about 60C at load. The Antec 900 also helps with that.

And sorry, I think you did just get unlucky with your processor. But still, a C2D at about 3Ghz is still really nice. It's not like you're missing out on too much.

i think you have miss one very important note when overclock.no 2 CPU overclock the same.and from 3 CPU you see OC past way higher but how much does that represent the total number out there?

a bad yield core could stop you from OC higher,and so will a bad quality mobo.

just set you ram devider to 1:1 so over 416 will get you 832mhz rather than 998mhz.if the ram speed is higher than FSB dont mean you will get better performance.1:1 will get you the real performance.if you dont do that it will just put extra unnecessory strain on the memory.

by doing this,if you are lucky you might able to do 450x7@3.15Ghz and nice healthy 900Mhz with 4-4-4-15.because from my experience 900mhz being the limit before you have to raise the latency to CAS 5 with voltage 2.1V-2.2V at any speed above 900mhz.

just to let you know C2D above 3Ghz will eliminate the CPU being the bottle neck in gaming and it will be all down to your GPU.

Good luck!

Thanks iluvgillgill. Pretty much the answer i was looking for. Thanks for the info and heads up on C2D over 3GHZ