Abit owners...

[HardWired]

I posted this in the motherboards|Abit IS7 thread and it hasn't received a response in the last few hours so I'm posting it here in hopes of a response.

Last night I got my new rig together and I'm missing my Asus P4PE already. The overclocking on it is/was so simple. You set the FSB mhz. that you want and you choose out of 3 settings the mem MHz. that you want. Too easy.

After installing my IS7 last night ...quite frankly I don't know where to begin when overclocking it. As far as the BIOS settings go, I don't understand what the game modes are about, the CPU THRM Throttling setting, nor the references and settings regarding RAM dividers and/or operating ratios.

Can someone give me quick starters guide on how to sucessfully o'c a 2.6c? Assuming the CPU will cooperate

Which do I start moving in which direction?

The rundown on my system is as follows. An IS7, a 2.6c, two 256MB sticks of OCZ PC4000 EL Gold, and a 9700 Pro modded with all four hard mods. This is all being powered by a new Antec TrueControl 550W, which I must say is the sweetest PS (out of many) I've owned to date.

I can get some hints from browsing through the 16 pages in the mobo forum/official thread, but nothing real concrete that will sharpen the learning curve in a short amount of time.

THX!!

 

[Sunny129]

in the BIOS under the SoftMenu III section, you'll find fsb settings. now because you are using the 2.6C, the default fsb will be set to 800mhz (200mhz system clock). now start w/ a safe OC, like 3GHz. to get the 2.6C to 3GHz, you will have to raise the fsb to 231mhz manually. at 231mhz system clock, the DDR memory will be running at 462mhz, which is approximately PC3700. you have PC4000, so you will have no problem running your memory with a 1:1 divider at that particular system clock. in fact, your PC4000 is really DDR500, which is memory rated to run at 500mhz. and to run your memory at 500mhz with a 1:1 divider, the fsb will have to be at 250mhz, which will result in a CPU OC of 3.25GHz. just start w/ a 3GHz OC (231mhz fsb), and a memory divier of 1:1, and go from there. proceed by raising the fsb in 5mhz increments until you start getting stability problems. once you've reached what you feel is the limit of a stable OC, test system stability by running prime95 for 24 hours or something. let me know how it goes...

EDIT: leave GAT settings on auto and CPU throttling at their default settings until you've reached your OC and tested the system's stability...then play with them to see if you notice a performance difference.

also, a couple of pointers once you start playing w/ GAT settings. now GAT is really just an emulation of the PAT settings integrated into i875 chipsets, therefore there are limitations on GAT. for instance, i believe GAT doesn't work at all while using memory dividers other than 1:1, despite what the motherboard may allow you to set it at. also it has been said that it also doesn't work above certain fsb speeds, but you'll have to post a question about that, or search through some old threads for an explanation to that, b/c i do not specifically know for what fsb speeds this is true...

 

[HardWired]

Thanks Sunny129...

What you gave me was kind of a beginners "how-to" on overclocking, which I'm already well versed in. I had my 2.53b cruising right along at 3.3GHz. on a Asus P4PE, which is now my wifes rig.

What I'm more curious about is the memory divider issue, which I haven't had to deal with in this way before. Like what's the difference between 5:4 and/or 3:2, and which direction does it take the ram on the MHz scale when changing it.

I see the new MHz. when changing the CPU speed... that one is obvious. But I don't see where it shows at what speed the memory is running...unless I'm just missing it somewhere.

Also, when you refer to GAT, is that just the "Game Accelerator" entry in the BIOS, or is GAT referring to "Game Accelerator" and the four underneath it? If GAT only refers to "Game Accelerator", what settings should:

Refresh Cycle Time
Read Delay
Read Delay Adjust
Command Per Clock

be at? And one last question, the reference to N/B Strap (I'm assuming NB is for NorthBridge) that's another BIOS setting I'm not familiar with. Should that be left on "By CPU", or is there a better setting for it depending on what's being done with the RAM/CPU settings?

 

[Duvie]

I have a 2.6c on the way as well and will be going into the IC7 mobo......

First you should change the N/B strap to 800mhz as this will open up the dividers specific to that processor like the 5:4 (not to be confused with 4:5 associated with 533fsb chips) and 3:2....

I am sure you are eyeing 3.5ghz as well as me....At 3.5ghz it will take 270fsb....

270fsb w/ a 5:4 ratio will be 216fsb x2 for 432mhz ddr or pc3500 rated speed.....Use this with any speed rated equal or higher or good ocing pc3200 stuff.

270fsb w/ a 3:2 ratio will be 180fsb x 2 for 360mhz ddr or close to pc3000 stuff....


obviuosly you can tell the ratio of 5/4 means to take system fsb like 270 divide it by 5 to get 54 then times by 4 to get 216mhz...ddr then double pumps that (x2) to go to 432mhz ddr....




I would leave all gat or pat at auto with the last 2 items in that area of the bios disabled. Those are only effective with 1:1 ratio sosounds like unless you have some rocket ship pc4000 or pc4200 tou will not be using 1:1, but still disable the last 2 items. Read delay adjust : disabled.....CPC check : disabled...all the rest auto

Abit mobos report higher temps then the most so I would set the thermal restart temp at like 75 or greater. P$'s own cpu throttling is still scheduled to turn on by its own standard and burn-up other then overvoling is uheard of.

 

[Sunny129]

Duvie explains it great, and he also seems to know specifics about the Game Accelerator you are referring to. i was referring to the whole section in the BIOS, not just the top option, but i might go back and set mine up like Duvie suggested. the mem ratios are exactly what they seem to be. if the fsb (system clock in the SoftMenu section) is set to 250mhz, and you don't have memoory capable of DDR500 speeds, then you can't use a 1:1 divider (which just means that the memory is operating on the same frequency as the system clock of 250mhz, and since the memory is DDR, it is effectively running at 500mhz). so a 5:4 divider for example may be more appropriate. this means your mem will be running at 4/5 the speed of the fsb, i.e. 250 / 5 * 4 = 200, and this is a good divider for someone who has PC3200 and doesn't want to OC their memory or is already OCing their lower rated mem and it won't go any higher, because 200mhz is in effect 400mhz DDR.

now if you had an old P4A CPU that ran in the 400mhz fsb and set the N/B strap appropriately, a different set of mem dividers would be available for use. for example if i wanted to run my 1.6A @ stock 1.6GHz, it would do so by default on a 100mhz fsb. but if i had PC3200 (DDR400) mem, it would be running at half its rated speed on a 1:1 divider, i.e. 100 / 1 * 1 = 100mhz = 200mhz DDR. and so you'd also see other dividers that work in the opposite direction as before, such as 2:3, 4:5, and maybe 5:6. 2:3 is the broadest of the 3 dividers, so lets use that: 100 / 2 * 3 = 150mhz = 300mhz DDR. so still, if i have DDR400 mem, the fastest i can get it to run using an N/B strap of 400 is 300mhz, which is obviously below stock, but its better than the 200mhz it would be running at on a 1:1 divider. i hope this explains the divider thing a little bit better than i had before.

 

[HardWired]

Okay, thanks guy.

I'm currently running it at a 250 FSB with the ram set to 1:1 and it seems very stable with a stock CPU vcore and the sys. temp at 33-35c and the CPU temp around 40c to 44c using a SLK-900 and low RPM Panaflo 92mm.

While I'm going to go slow, I want try and get around this rig to around 3.5 Ghz. stable, and your comments go a long ways towards helping me figuring this all out.

Thanks again...

 

[fpok]

Howdy yall,

First post in this forum, and its in the OCing section, woot!

Here are my NON STABLE settings:

FSB: 245
N/B: By CPU
DRAM Ratio: 5:4
AGP Ration: Fixed

CPU: 1.575
DIMM: 2.8

Mem Timings:
CAS: 2.5
Act to Prechg: 7
RAS to CAS: 3
RAS Prechg: 3

GAT: Auto
(1): Auto
(2): Auto
(3): Auto
(4): Auto

CPU production specs:
Code: SL6WS (Malay)
Batch: Q337A314
Pack: 10/14/03


I just bought the IS7, P4 2.6C and Geil Golden Dragon PC3500 2x512 [2.5-6-3-3].

I can only OC to 230FSB 1:1 [2.5-7-3-3]. The Mem voltage is 2.8V and CPU temp is a 33C...even at 1.575V. I dont think the CPU is holding me back at all. I was able to boot at 245FSB but windows was not stable/Prime95 crashed. Temps still stayed around 33C.

I see some people using all auto for GAT and some disabled settings. I tried all auto and no OC gain?same as when I disable the last 2 settings. I also have trouble verifying if PAT is enabled (or I dont think it is enabled). Any pointers appreciated.

I tried relaxing the memory as well (CAS 2.5 --> 3) and I get bios/boot errors. How did y'all go about relaxing your timings? I saw some examples above for [2.5-8-4-4] so I will try that out.

I am guessing having trouble with the 5:4 mem divider. I am sure I am missing a setting somewhere. Can you give me some info on your mobo settings? FYI, I am on the 1.7 BIOS.

Cheers,

 

[fpok]

UPDATE:

I can take this to 230FSB 1:1 stable, vCore 1.575v. I am burning in 235 1:1 [2.5-8-4-4], vCore 1.575v, as we speak.

So, 230 * 5 / 4 = 287.5 FSB potential. I still cant get the mem to stay stable at 250FSB 5/4 (DDR400) with manual [2.5-6-3-3], [2.5-7-3-3], [2.5-8-4-4] or SPD [2-5-3-3].

I had to up the vCore to 1.625v to get 260FSB to load windows...but still coulndt figure out the mem issue.

I have tried combinations of GAT at AAAAA or AAADD and NB by CPU or 800, and still no luck.

I dont understand why my Giel will not run at DDR400 using a 5/4 Divider. Is the mem bad or is it the mobo?

Cheers