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**Nickel020** · 02-20-2009, 12:31 PM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

I don't have time to reply to the whole post right now, but I can give you a few quick answers: At 1:1 FSB and RAM bandwidth is exactly the same in dual channel mode. Increasing the RAM frequency basically improves latency a little bit, but that's not really a big deal, neither is fine-tuning the timings. You'll see improvements in things like SuperPi or memory bandwidth benchmarks, but start up a game benchmark and you'll hardly see a difference. At least in current ones that are somewhat GPU limited, in old CPU limited ones you may see a bigger difference, but it doesn't really matter whether you have 200 or 220 FPS there.

If you're considering spending time tuning your timings you should instead consider overclocking. Even a small overclock will bring a much bigger improvement than tuning timings ever will.

**Dalamar** · 02-20-2009, 01:04 PM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

Originally posted by Nickel020 View Post

I don't have time to reply to the whole post right now, but I can give you a few quick answers: At 1:1 FSB and RAM bandwidth is exactly the same in dual channel mode.

Right, this is exactly what I'm going for.

Currently my available memory bandwidth is:
533MHz x 2 transfers/clock (DDR) x 16 bytes (2x 64-bit, dual channel) = 17,056 MB/s

At the moment my stock FSB bandwidth is only:
333MHz x 4 transfers/clock (quad pumped) x 8 bytes (64-bit bus) = 10,656 MB/s

For FSB that's a deficit of 6,400 MB/s, or about 37% less than the memory is capable of delivering, which is what I want to correct.

Originally posted by Nickel020 View Post

Increasing the RAM frequency basically improves latency a little bit, but that's not really a big deal, neither is fine-tuning the timings. You'll see improvements in things like SuperPi or memory bandwidth benchmarks, but start up a game benchmark and you'll hardly see a difference.

I'm not looking to increase RAM frequency. I want it to stay at stock (533MHz, or 1066MT/s). I just want to boost FSB to match it so that I can use all the available memory bandwidth, while holding everything else as close to stock as possible. I'm interested in learning what BIOS controls and voltages to adjust to achieve that.

Are you saying that bringing the FSB up from 333MHz to 533MHz while holding my CPU and memory at/near stock won't make that much real-world difference? I'd think an extra 37% in usable bandwidth between CPU and RAM would make a significant impact.

**Nickel020** · 02-20-2009, 01:59 PM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

If you increase the FSB as well then you might as well overclock, as technically you're not running your CPU within its specificatiosn anymore and you've voided your warranty (Intel can't tell though :))
You will see see mroe of an icnrease in performance than by pure performance, but you will probably have to increase the CPU voltage if you're aiming for 533 FSB. All in all, a 100 to 200 MHz will bring you more performance though I think.
The Core 2 CPUs have so much cache that they don't really benefit from extra RAM bandwidth all that much afaik.

But if you want to try it go ahead, you can't really break anything. Would be nice if you were to post some benchmarks!

**Dalamar** · 02-20-2009, 02:11 PM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

Originally posted by Nickel020 View Post

If you increase the FSB as well then you might as well overclock, as technically you're not running your CPU within its specificatiosn anymore and you've voided your warranty (Intel can't tell though :))
You will see see mroe of an icnrease in performance than by pure performance, but you will probably have to increase the CPU voltage if you're aiming for 533 FSB. All in all, a 100 to 200 MHz will bring you more performance though I think.
The Core 2 CPUs have so much cache that they don't really benefit from extra RAM bandwidth all that much afaik.

But if you want to try it go ahead, you can't really break anything. Would be nice if you were to post some benchmarks!

Well, I'll be slightly overclocking (from 3.0GHz to 3.2GHz) even in this setup, since I can't go lower than a 6.0 multiplier.

Are you saying that the CPU will need a vCore increase even if I'm lowering the multiplier to keep the core speed within 200MHz of stock?

Thanks for your replies, by the way. Sorry for all my questions, but I just want to make sure I'm understanding things correctly.

**Nickel020** · 02-20-2009, 02:23 PM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

Are you saying that the CPU will need a vCore increase even if I'm lowering the multiplier to keep the core speed within 200MHz of stock?

Will probably need it.

**Dalamar** · 02-20-2009, 04:24 PM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

Originally posted by Nickel020 View Post

Will probably need it.

Got it.

Ok, so I'll probably want to bump MCH core voltage and perhaps CPU vCore.

Do you think I'd need to worry about termination or reference voltages for either CPU or MCH to get to 533, or is it mainly the MCH core voltage that will determine stability at high FSB speeds?

Also, if you can confirm my understanding about the MCH strap functions that I mentioned in the first post, that'd be greatly helpful as well. I'm assuming I should stick with the 400 strap, since I'll definitely be above 400MHz on the FSB and would want the loosest timings possible to keep the MCH stable. Is that right?

Thanks!

Oh, and once I've actually got something working I will definitely post before vs. after benchmarks. I'm curious now too to see what difference it'll make.

**Nickel020** · 02-20-2009, 07:21 PM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

I hiope you have an E0 stepping, if you have a C0 you might be unlucky and not even hit it at all.
You will probably need some Termiantion, MCH maybe +0.1V. But there's not much point speculating, just try it.

**Dalamar** · 02-20-2009, 09:35 PM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

Originally posted by Nickel020 View Post

I hiope you have an E0 stepping, if you have a C0 you might be unlucky and not even hit it at all.
You will probably need some Termiantion, MCH maybe +0.1V. But there's not much point speculating, just try it.

Yup, I have an E0 (SLB9J). Going to try some settings now. Hopefully I'll be back later tonight with successful results.

**Dalamar** · 02-21-2009, 05:46 AM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

Well, I've found a few things that sort of work.

I can achieve 533MHz FSB (x6 for a 3.2GHz CPU) that will boot into Windows, but isn't Prime stable, by doing the following:

Set Host Freq manually to 533
Set multiplier manually to 6
Leave (G)MCH Latch at auto
Set Memory Multiplier to 2.00B or 2.00D (both result in 1066 Mem)
Set (G)MCH core voltage to 1.20v
Manually specify my memory timings and voltage (5-5-5-15, 2.1V)
Leave all other voltages at "normal" and all other options at default or auto settings.

It'll only prime for about 10 min though, so there's still something that needs tweaking. I tried bumping MCH core to 1.30, and even CPU vcore to 1.30 as well, but it still wouldn't prime more than 10-15 min, so I suspect one of the other timing or voltage controls needs manipulating.

Oh, and I did see a hefty bump in Sandra (v2009.1.15.72) memory bandwidth. Here are the averages of three runs for before and after.

Stock
(333MHz FSB x 9.0 for 3.0GHz CPU, 533MHz RAM at 5:8 FSB:RAM ratio)
Int: 6773 MB/s
Float: 6767 MB/s

FSB Overclock
(533MHz FSB x 6.0 for 3.2GHz CPU, 533MHz RAM at 1:1)
Int: 8831 MB/s (a 30.3% increase)
Float: 8807 MB/s (a 30.1% increase)

Considering the CPU speed only increased 6% it looks like I'm successfully making use of more of the available bandwidth of the DDR2-1066 memory.

Now I just need to figure out how to get the configuration 24-hr Prime stable.

Any suggestions on what settings to turn to next?

**Nickel020** · 02-21-2009, 05:56 AM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

The memory bandwidth benchmark is synthetic, improvement doesn't matter unless you get some actual performance improvement in a real application. Try benching with Crysis (demo) or even 3DMark, which is also synthetic but a lot less synthetic/closer to reality than Sandra or Everest.
You may need to increase CPU termination to get it stable and further increase VCore. Don't look at the BIOS setting of Vcore though, just look at the result in CPU-Z, You can also compare that to your VID (stock voltage) as shown by Core Temp.

**vacapp** · 02-21-2009, 06:43 AM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

Hi!

I think you are trying to achive your performance the same way as me (little CPU overclock, but as much memory performance as possible). Althought I am new in this OC scene, and have somehow different problems because of very small stock FSB (E5200/200MHz) I can show you some really helpful guides in my own thread (if you are familiar already, then never mind),(thread > http://forums.tweaktown.com/f69/ep45...se-help-30512/)
but the most important/useful are the followings I think:
1.) AnandTech: ASUS ROG Rampage Formula: Why we were wrong about the Intel X48
2.) AnandTech: Overclocking Intel's New 45nm QX9650: The Rules Have Changed
A really detailed info about timings-tRD-FSB-latency-performance overcross

I try to figure it out, how can I use these info in my situation also (small FSB). Not a very easy stuff.

**Dalamar** · 02-21-2009, 04:12 PM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

Originally posted by vacapp View Post

Hi!

I think you are trying to achive your performance the same way as me (little CPU overclock, but as much memory performance as possible). Althought I am new in this OC scene, and have somehow different problems because of very small stock FSB (E5200/200MHz) I can show you some really helpful guides in my own thread (if you are familiar already, then never mind),(thread > http://forums.tweaktown.com/f69/ep45...se-help-30512/)
but the most important/useful are the followings I think:
1.) AnandTech: ASUS ROG Rampage Formula: Why we were wrong about the Intel X48
2.) AnandTech: Overclocking Intel's New 45nm QX9650: The Rules Have Changed
A really detailed info about timings-tRD-FSB-latency-performance overcross

I try to figure it out, how can I use these info in my situation also (small FSB). Not a very easy stuff.

THANK YOU, vacapp!

Those two Anandtech articles were HUGELY helpful and exactly what I needed to educate myself about the intricacies of the current Intel platform and memory performance.

I now understand why the quest for a 1:1 memory ratio isn't worth the effort.

I will now be pursuing a configuration using 400MHz or 450MHz FSB and attempting to adjust the memory multiplier, timings, and and particularly tRD to maximize performance.

A question, on Gigabyte boards is tRD the "Static tRead Value" setting for each channel?

**kick** · 02-21-2009, 05:34 PM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

Id load up memset,linked in the memory setting sticky above to find out about the timings.
Me personally my fsb/memory/cpu combination is just about right.
I was lucky in the memory,I didnt know it would run 1000mhz when i bought it,I just wanted the tight 4-4-4-12 timings at 800mhz on ejec voltages as my previous GA 73pvm s2 board has no mem voltage adjustment.

If you want a lot of detailed bandwidth readouts use cacheburst.
It will generate memory reports rapidly,but it gets a bit too detailed for posting.

**vacapp** · 02-22-2009, 06:15 AM

Re: Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

Originally posted by Dalamar View Post

...
I will now be pursuing a configuration using 400MHz or 450MHz FSB and attempting to adjust the memory multiplier, timings, and and particularly tRD to maximize performance.

A question, on Gigabyte boards is tRD the "Static tRead Value" setting for each channel?

You are welcome. I spent a whole week to find this exactly fitted information according to my problems. Still, I am not finished yet because of the mentioned small stock FSB (what happens below 400MHz? Therefore is no hint, I must calculate it for this special case). But it seems I ve found the right informations. If you need some timings and other stuff like voltage, lifetime:
1.) TTR's Guide to Determining Optimum Overclocked System Performance Points - The Tech Repository Forums
2.) How memory frequency affects latency - Tighter timings vs. Higher speeds? - The Tech Repository Forums
3.) AnandTech: Intel's 45nm Dual-Core E8500: The Best Just Got Better

Althought I am still studying these new information (1. and 2.) compared to Anandtech (whether they are related and reliable) I share this of course.

As for tRD it is the Static tRead Value in BIOS and called Performance level setting in Memset Tweakers.fr (you should not save only apply in Memset and test, so you can reboot the pc if the lower setting not works).
After tests seems OK, you have to change for both channels - if you are running dual channel - the same value in BIOS.

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Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

Help understanding GA-EP45-UD3R BIOS settings & Core2 FSB OC principles

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