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Blacklash
06-24-04, 10:54 PM
We all have to start some where. If you have ever wondered how do I set
all those numbers in my bios to control ram latency, here's a place to start.

I found this fellow's comments on tRAS particularly interesting. It's a nice basic upfront explanation. If you own an Abit IC7-G like I do you will find the GAT(Game acceleration technology) will optimize your ram for you if set to auto or turbo. My old crappy value select corsair 3200 was rated 3 3 8 2.5. Yet when I viewed my actual settings in windows with CPU-Z they were listed at tRAS-5 tRCD-3 tRP-3 CAS-2. I want to run my OC 3500 at 7 3 3 2 on a 230x4 FSB.

Here's the link:

http://www.ocfaq.com/article.php/overclocking/63

jAkUp
06-24-04, 11:06 PM
hmmm.. the memory timings I set in my bios (IC7) were..
245FSB: 1:1 Ratio

2.5
5
4
3

Im trying to understand if those are correct, or incorrect... They were the lowest I could set them on my board without being unstable. Now I think I may have set them incorrect.... For some reason the GAT on my board doesnt work correctly... As soon as I move it from auto it doesnt post

Strange how it lists my memory as 3700....

Blacklash
06-24-04, 11:18 PM
JakUp grab CPU-Z from here.

http://www.cpuid.com/cpuz.php

Set your GAT to all Auto and your latency to "By SPD", not manual. Your bios screen will not show them changed but CPU-Z will. Just see the memory tab when you boot.

I have found selecting by "SPD" and Turbo under the first slot of your GAT with the rest to all auto to give the best performance. If it still doesn't post try Turbo, Auto, and the last two to disable. Your GAT can force better timings than you can set manually depends on the RAM. It's really nice to try if you had average rated RAM like I did that was actually way better than its rating. If is still doesn't post under any of these scenarios then GAT is not compatible with your RAM. Another possibility is that the GAT is trying to assign latency values that are too aggressive at your FSB setting. I know when I went 3.5 at 5:4 on my old set up I couldn't use GAT. It was too demanding.

When I overclocked my old 2.8c to 3.2 with SPD assignment and turbo I got up to a 5640 read in AIDA32.

EDIT Odd recognition. Unsure about that unless it is rating it by closest frequency which is 466 for 3700.

jAkUp
06-24-04, 11:37 PM
Ok, first I tried by spd, then everything at auto, the voltage is at 2.8
http://www.nvnews.net/vbulletin/attachment.php?attachmentid=6566&stc=1

Then I tried setting GAT to turbo, everything else auto... And I got a BIOS checksum error...

Then I tried GAT to turbo, Auto, Auto, and disabled, disabled... Same BIOS checksum error :(

Im guessing this ram just doesnt like GAT... so would the timings I have set manually be ok?
This is what I have set manually:
http://www.nvnews.net/vbulletin/attachment.php?attachmentid=6565

Also, I have read before that setting BIOS cacheable to disabled, and video bios cacheable to disabled increases performance.. I'm just curious if its true

Blacklash
06-24-04, 11:51 PM
I think your FSB may be running just a tad high for Turbo,

I would say bench to test both settings with UT2004 at 640x480, 3dmark2003 and maybe SiS "Sandra" as well. I doubt there will be a huge difference. I know the lower CAS is pretty much the thing that delivers performance.

I would also say try your manual settings again using this fellows idea that tRAS should be a sum of tRCD, CAS, and 2.

So bench and experiment!

jAkUp
06-24-04, 11:53 PM
Sounds good :) THnx

Rytr
06-25-04, 12:10 AM
I had some success with GAT but I prefer manual. Of course I wanted to find the limits of my system with the IC7. Ended up with 286 FSB as max which took considerable work. Anyway, I settled on 250 FSB, 1:1, 2.5-4-4-7, (which BTW is the ram mfg's recommendation) and I am satisfied with the stability/performance running 24/7. With this setup my bandwidth is 5732 MB/s ram int buffered, 5800 MB/s ram float buffered as identified in Sisoftware Sandra Pro.

Blacklash
06-25-04, 12:39 AM
I might mention there are two schools out there.

People that prefer the absolute tightest timings you can get and those that go for the absolute largest FSB overclock. The latter school is much more suited to Intel, and the former AMD.

What was odd with my 2.8c overclocked at 3.2 234FSBx4 1:1 I had a better mem read of 5640. While at 3.5 which was 5:4 250 FSB I had better FPS in games but only a 5454 mem read.

I think it is worthy for you to investigate the loser timings JakUp. Heck you may even be able to up your FSB to 250.

I have looked at A LOT of memory reviews in the past few days and one thing stands out. Tight timings like 6 2 2 2 rule the roost at 400/433DDR, as you approach 466 frequency rams that have slight looser timings like 7 3 3 2 start to pass them up in game performance. I would definitely experiment. *Chuckles* What I am saying is in the Intel Mobo world big arse FSB can offset looser memory timings.

I wanted a 30cap 3.0c like yours JakUp but was afraid I'd get a 12 cap instead. I plan on trying this 3.4 well into 3.8 maybe 3.9 when I get my RAM.

and to Rytr your rigs seems fine to me! Anything approaching 6000 MB/s is awesome.

I will post up my readings when I get my new RAM in!

Rytr
06-25-04, 04:55 PM
I agree there is signifigant difference in the approach to ram timings between Intel and AMD. My MSI (AMD) board uses timings of 2-3-2-6, 1:1, 220 FSB which is much tighter than I use on the Abit IC7 (Intel) board. Bandwidth results on the AMD are 3304/3301 MB/s with the timings I use. The ram is capable of 2-2-2-5 but I prefer the less stressful settings and still get very good gaming performance.

Blacklash
06-25-04, 08:20 PM
I agree there is signifigant difference in the approach to ram timings between Intel and AMD. My MSI (AMD) board uses timings of 2-3-2-6, 1:1, 220 FSB which is much tighter than I use on the Abit IC7 (Intel) board. Bandwidth results on the AMD are 3304/3301 MB/s with the timings I use. The ram is capable of 2-2-2-5 but I prefer the less stressful settings and still get very good gaming performance.

Can't argue with that. Seems like we are on the same page. I am learning through experience there is quite a difference between peak bandwidth and effective bandwidth. I got my P4 3.4c today but I am waiting on the ram and a zalman 7000A-Cu after market HSF before I install.
I want to make a good seal with arctic silver 5 hopefully only once and leave it at that. I am going to try for 3.9 with my ram around 230 and 2-3-3-7. We will see how it goes.

When I completely rebuild my system late next summer/early fall I will probably try the AMD side of the tracks this time.

Rytr
06-25-04, 10:54 PM
Malficar,

I like 'em both. What works is best, IMO, and both work well so I really don't have a favorite. The only favorites I have had was the Iwill boards (KK266R and XP333R).

The 3.4C has been turning in some impressive numbers. You are going with some tight ram timings for an Intel setup but should have no problems going 230 FSB or maybe even better. I tried 2-3-3-7 with my setup but stopped at 225. Still seemed to have plenty of headroom but just got a wild hair to go max FSB and never went back to tightening up the timings. Maybe I should give it another go. Good luck and let us know how it goes.

Blacklash
06-25-04, 11:55 PM
Rytr,

Can you suggest some memory/system stress test tools for stability?

I couldn't stand it and I popped my 3.4 in and booted up to 3.9 in windows. I am stable on my desktop anyway. 230X4 with my old ram :D

I am on 44 degrees celsius with the stock cooler and arctic silver, but I just booted so I expect a drop in temp.

I can't wait for that zalman.

First conservative attempt:

http://img8.imageshack.us/img8/5421/firstfewboots.jpg

Bad_Boy
06-26-04, 12:05 AM
i was kinda wondering. what can i expect in games if i were to get tighter timed ram?

thx in advanced.

Rytr
06-26-04, 12:12 AM
Rytr,

Can you suggest some memory/system stress test tools for stability?

I couldn't stand it and I popped my 3.4 in and booted up to 3.9 in windows. I am stable on my desktop anyway. 230X4 with my old ram :D

I am on 44 degrees celsius with the stock cooler and arctic silver, but I just booted so I expect a drop in temp.

I can't wait for that zalman.

Well, for memory memtest86 has continued to be good as well as looping on of the more stressing synthetic benches.

For stessing the card I continue to use 3DMk2001se, 2003, and AM3 (if something is no right one of them usually shows it) then on to playing actual games which is the real-world test, IMO.

For system testing lately I have just been running Folding@Home for 48+ hours. There are a number of others I have used such as Sisoftware Sandra Pro's 'Burn In', and Prime95 v2.34. Also, I just set down a play a cpu stressful game for a couple of hours and watch for stuttering, anomolies, and of course, crashes to the desktop or BSOD. :D

BTW, I especially like the cpu voltage you are running in your first attempt...should definitely help with cooling and should work with the Zalman well. :) Do you plan to use the Zalman without a fan?

Rytr
06-26-04, 12:26 AM
i was kinda wondering. what can i expect in games if i were to get tighter timed ram?

thx in advanced.

Its kind of a mixed bag. For the most part it seems the Intel boards get a little extra using moderate loose timings with a high FSB for gaming. I have not kept up with it lately so things may be changing. Let's see how Malficar experiences go. He is off to a good start on the overclock! (popcorn)

Blacklash
06-26-04, 12:37 AM
Its kind of a mixed bag. For the most part it seems the Intel boards get a little extra using moderate loose timings with a high FSB for gaming. I have not kept up with it lately so things may be changing. Let's see how Malficar experiences go. He is off to a good start on the overclock! (popcorn)

I will truly push it soon as I get my Zalman. It shipped tonight, and is on two day air. So check back early next week and I will have some real numbers for you. I don't expect air on the stock HSF to go much further. I am idling at 42C
at the stated OC. Sis Sandra's memory&cache bench will send it all the way up to 58C briefly at 3.9. So I am going to hold off on stressing it. I hope to touch at least 4.1 and break 6000 MB/s. This old ram has to go. If I can get 245FSB out of the OCZ with CAS 2 I will be very happy, CAS 2.5, mildly happy. That will put me right at 4.165. Or IMO a nice OC.

Now if I can just get my BFG-OC 6800 GT to do 420/1020(Or so) I will be set.
*Thumbs his nose at Far Cry* :D

On the voltage, I want to hug 1.6 as long as possible. I really hate to move up to 1.675, but I have heard a few fellows say if you want to go out of 3.9 and break 4.0 it's highly likely. I contribute my ability to use lower voltages and some OCing I do in general to this wonderful well shielded, stable enermax 550 PSU.

BTW thanks for the advice on the mem program.

EDIT the zalman 7000A-cu has a fan. This is the one.
http://www.newegg.com/app/ViewProductDesc.asp?description=35-118-109&depa=0
I am definitely keeping the side off my case, and regularly cleaning with compressed air.

The only thing better I could get on air would be a Thermalright SP94, with a Vantec tornado 92mm. I don't want the noise though, or the task of removing my motherboard again. I am hoping arctic silver 5 lends me enough edge for it not to matter.

Rytr
06-26-04, 01:45 AM
I've got the Zalman with the fan setting on the shelf waiting for the right card to use it on...forgot it was the A-cu model. :retard: So, I hope for your success in more ways than one! ;)

Blacklash
06-26-04, 02:24 AM
I've got the Zalman with the fan setting on the shelf waiting for the right card to use it on...forgot it was the A-cu model. :retard: So, I hope for your success in more ways than one! ;)

Thank Rytr,

May the OC Gods continue to smile on you as well.

Bad_Boy
06-26-04, 10:48 AM
thx Rytr

i asked because i got a oc that im satisfied with and im thinking about getting that corsair xms 2-2-2-5 ram. trying to learn the benifits of it. but im kinda worried i wont get a decent oc going from pc4200 to pc3200.

Rytr
06-26-04, 12:45 PM
thx Rytr

i asked because i got a oc that im satisfied with and im thinking about getting that corsair xms 2-2-2-5 ram. trying to learn the benifits of it. but im kinda worried i wont get a decent oc going from pc4200 to pc3200.

Overlooking the price the benefits of the XMS 2-2-2-5 will be minimal if any, IMO. You, more than likely, will not be able to get your present oc that you have with the PC4200 and possibly will not be able to improve performance. If it was AMD my opinion would be different, in fact, I have Mushkin PC3200, 2-2-2-5, running on a NF2 board with a Barton right now. Just started playing with it and so far its running 216 FSB (PC3500) in dual channel.

Again, I would suggest you hold off and see how Malficar's experiment pans out before you invest in ram with tighter timings for the Intel board.

Bad_Boy
06-26-04, 01:14 PM
ah ok. thanks :)

Blacklash
06-26-04, 02:12 PM
thx Rytr

i asked because i got a oc that im satisfied with and im thinking about getting that corsair xms 2-2-2-5 ram. trying to learn the benifits of it. but im kinda worried i wont get a decent oc going from pc4200 to pc3200.

Definitely good advice from Rytr,

You will find the low latency rams rule the roost in their rating area usually 400-433, as soon as you start to approach 466 rams like OCZ 3500 EL and up start to do well. The latest Corsair top ram can do very high FSB settings however it does not match the good 3500/3700 ram for 466 and up at gaming performance. If you are not exceeding 250 FSB I consider PC4000 a waste.

So benefit from my experiment as Rytr said, and if you are not going greater than 433 consider the 3200 2 2 2 5 rams. If you want to have the larger FSB go 3500/3700. Look at Corsair, Mushkin, and OCZ, in my opinion.

Example: here is the best Corsair 3200 memory you can buy at 466:

http://www.anandtech.com/memory/showdoc.html?i=2082&p=10

EDIT: Highest 1:1 Overclocks:

http://www.anandtech.com/memory/showdoc.html?i=2082&p=12

I would experiment with the idea that, reading from the top of your bios ram latencies, the value for slot 4 should equal slot value 1 and 3 plus 2, or for low latency actually 2 2 2 6 instead of 2 2 2 5. (tRAS=tRCD+CAS+2)

JoKeRr
06-26-04, 07:23 PM
hm, long live the BH5, 250 1:1!!! damn, need Vdimm mod...
as for CPU cooling, right now the king of hill is Hyper 6 by Coolermaster. but it's over 1 KG!! in weight. Can't wait till Thermalright XP 120 comes out, light aluminum, 120 mm CPU fan!! Yeah!!