2.8C - Free swap to 3.2E worth it? (s478) (AI7 MB)

[pedwar]

Hi,

Sorry for another of those annoying 'what should I do, Prescott/Northwood' posts, but I just wanted to guage peoples general opinion..

I've got the oppertunity to possibly swap my P4 2.8C Northwood for a P4 3.2E (Prescott) for free. Is it worth the swap?

(both s478 of course)

I was going to buy a 3.4C, but unfortuantely the shops are all now sold out of this chip. I'm tempted to get a 3.4Ghz Extreme Edition CPU, but I'm wondering if it's worth the extra cash at the moment.

The main thing that puts me off the Prescott is the heat (it would be cooled with my trusty Thermalright AX478), and I'd probably run a 215Mhz FSB like I do now as that's the most I can get out of this ram.

The other thing that puts me off is the fact that after looking at several benchmarks across the web (including Tomshardware's review of the Prescotts a while back) my 2.8C actually beats the 3.2E in some tests, the main being Commance 4!!

As this is purely a gaming rig I wondered if I should just keep the 2.8 Northwood? (then again the 16x multiplier vs the 14x is more appealing)

What do you all think?

 

[aNTiChRisT]

Its not so much cooling the CPU than cooling the motherboard. Prescotts really push the power circuitry on the mobo, mostfets will heat up adding to the temperature of the whole case.

Northwoods tend to be better than prescotts until you start getting up to 3.6+ where the pressy's pull away. Prescotts tend to overclock better, but with such a modest overclock i wouldnt worry about it.

I would say? Keep the 2.8

Of course, you could swap the CPU, sell the 3.2 and buy a slow CPU again -- making a slight profit to get some new ram

~t0m

 

[pedwar]

Thanks for the quick reply.

I forgot about the MOSFETS on the board Another reason not to do the upgrade

Hmmm, I should really try and push more out of the 2.8 I've got, I'll try and up the voltage some more on the Samsung RAM and put it down to CL3, I'm sure it'll push more than 215FSB. I've always steered away from the 3:4 CPU RAM Divider as I've heard you can sometimes end up with slower performance with a higher FSB/CPU speed.

Can anyone think of any other sites that might have a 3.4 Northwood left in stock? I've tried all the big UK sites, and some of the US ones (tigerdirect.com, newegg.com, compusa.com but I can't think of any others (me not being US based)

Thanks again,

 

[Sucka]

I wouldn't ever go back to Northwoods personally. Once the Prescott hits ~3.6 it starts to dominate the Northwood's i owned prior (3.0/3.4C). Heat is an issue, but it just adds to the fun of overclocking Going with an EE would be the worst idea of all. Not only is it going to be old tech in a few months, but it's way overpriced, and hardly gives a boost over highly overclocked Prescott's. If you really want a beastly gaming chip, go A64. It's been proven time and time again that the AMD chips are much better in the gaming scene. Not trying to start a debate here, i own both and love both. But you did want an opinion.

 

[Jimbob7]

I dont know how other people feel about this, but a Prescott in a 865 chipset mobo isnt to good, and your overclock will be limited alot, because of the pressure put on the board.

 

[Lancelot]

Hah! I did it exactly the other way around! I had a dog 3.2E C0 that didn't do anything above 3.4 3.45ish, and even that was with high Vcore and tremendous heat. Then I could swap with someone who doesn't OC but had a M0-step 2.8C in his system. I took the plunge and here I am @ 260FSB 3.64Ghz dual-Prime stable. 265FSB is still 24/7 stable and I can get into Windows for a while @ 275FSB but I refuse to take it above 1.65Vcore. My point is if you aren't guaranteed at least a 3.6-ish speed with the Prescott then don't bother cuz you'll have less FSB and longer pipelines...

 

[Jimbob7]

Nice Lancelot, the 2.8 M0 overclocks great

 

[pedwar]

Thanks guys.. I think I'll be keeping my 2.8C for a while then, mine is a SL6Z5 chip too (I made sure they sent me an M0 stepping chip specifically when I ordered it)

(Just looking at the box now to check and it is definitely a SL6Z5, Costa Rica made? Hmmm)

Sucka: I have thought about trying AMD again one of these days but that would require a new board, and knowing me new RAM, then Graphics card etc. so think I'll stick with the P4 for now.

I upped the FSB to 220 last night and hit 3.1Ghz.. that ran memtest 4 times straight without a problem and 3dMark2001 in software mode for 30mins without a problem. (stock core voltage) Can't remember where I hit lasttime (about 8 or 9 months ago) and why I didn't push this further, I'm sure it was the RAM stopping me.

If so I definitely believe that Samsung ram takes a little time to 'burn-in' or settle down as I've seen this in two systems now. The system was burnt in for 24 hours when I first got it because of this. I might get the voltage up to 2.7v on the RAM and see how much more I can push it. Timings are at a terrible 3-3-3-8 at the moment. (stock) Maybe 2.75v someone said anything under 2.8v for Samsung should be fine (on heat spreaders on there tho)

I think the stock voltage was 2.6 and it's on 2.65 at the moment.

I might splash out on some Corsair XMS XL 2-2-2-5

Thanks again guys.

 

[larva]

You need to learn about what you have before you consider new hardware.

The i865/875 chipsets provide 1:1, 5:4, and 3:2 ratios (more are available by selecting something other than 800fsb cpu, but these are the ones of use to you). i845e had only a 1:1 and 3:4 mode, but even so the 3:4 mode was the only way to go. This is not AMD-land, Intel is a fully capable chipset designer well able to provide async modes that work.

You need to be running 5:4 mode with your 2.8c, and it should amount to a free upgrade in terms of the application performance increase.

 

[pedwar]

Hi Larva,

I was thinking of tinkering with the 3:4 and 5:4 Ratios, but I've always prefered to keep to the 1:1 ratio.

The Samsung RAM I've had was always a weakish point of my system, I should really get some Corsair or OCZ stuff..

Just messing around with it now, the FSB is now at 228 Mhz, RAM voltage was at 2.65v and it 3-3-3-8 and it failed the 2nd pass in Memtest

I've just upped the RAM voltage to 2.7v (I'm not going to risk taking it past that on that ram) and am just running through the tests again to see if it makes any difference.

RAM is cheap these days, so I wouldn't mind some nice Corsair stuff then I can run up to a 250FSB at 1:1. I normally only upgrade when I have a friend that will buy the old stuff off of me at a reasonable price. I don't want to leave good hardware wasting away on the shelf gradually becoming out of date while it's not even being used

Thanks for the advice though, I take it you're a fan of the Async modes on the 865 then? For 3D gaming I've always wanted to keep my memory throughput as high as I can, to get 200Mhz RAM speed I'd have to push my FSB to 250Mhz like yourself at 5:4, for another £150 or so of cash I could have 250Mhz 1:1

 

[pedwar]

Just failed the 4th pass of memtest at 228Mhz at 2.7v, so looks like the extra voltage made a slight difference, but not enough (of course it could jsut appear that way that 2.7v made it last longer, I'll let the tests run through more times to be sure as 4 passes isn't really enough sometimes)

Back down to 227Mhz @2.7v and testing again now..

 

[Lancelot]

Yes but that will be about the max. you'll get at 1:1. Larva, me and lots of others are running at 5:4 and eventhough this 'kills' your RAM performance as others like to put it, you really notice the higher core and FSB speed. I still haven't seen ANY benchmark that convinces me to run 1:1 at ALL costs. So just give it a try at 5:4 and see for yourself what your CPU has in it...

 

[pedwar]

I might give 5:4 a go then.. Anyone know of a bootable LiveCD OS that has good Sandra/ PCMark type software for good CPU testing? Don't really want to kill my XP install with corrupt files etc. (done that before overclocking 1Mhz too far on another machine ) (I don't mind memtest crashes for Ram testing as it's a bootable floppy)

Think I was just unlucky then though as that's the only time it hasn't come back from the BSOD

Has no one on here managed 250FSB 1:1 with some decent DDR500 RAM then?

If I could be bothered I could chuck another HD in there and stick a trashable build on there.

I guess with lower RAM speeds I could try some more aggressive timings to make up for it, I think I got it down to 3-3-3-5 lasttime at around 215Mhz. (maybe even 3-2-2-5 I can't remember now)

It's all good fun

Thanks again,

 

[larva]

Look at my signature and show me where 5:4 mode "kills" the performance. My machine's memory performance (and application performance) is absolutely first-rate for a 3.5GHz Northwood.

The problem with running 1:1 at 250MHz is that unless you have god's ram you will have to run slack timings to make the clock, and have no chance at enabling GAT. The timings and the GAT are much more important.

Your current ram (and cpu, and mb) may be capable of great things is you simply use them correctly. Spend some time reading here and you can both learn of exactly what works and how much better it can be. Start here:

http://www.ocforums.com/showthread.php?t=346778

 

[ewhenn]

Yes but that will be about the max. you'll get at 1:1. Larva, me and lots of others are running at 5:4 and eventhough this 'kills' your RAM performance as others like to put it, you really notice the higher core and FSB speed. I still haven't seen ANY benchmark that convinces me to run 1:1 at ALL costs. So just give it a try at 5:4 and see for yourself what your CPU has in it...

That depends on wher the chip wall and memory wall is. My chip poops out at 145 FSB (2.91 GHz). 1:1 yeilds 145 on my RAM.. My 4:5 yeilds 182 MHz. If I ran 5:4 it would not even hit stock speeds when my CPU clock is hitting the wall.

Now granted, my system is not exactly state of the art, but I like to start at 1:1, and seeif my chip poops out first.

 

[larva]

We were not talking about the 4:5 mode, but rather the 5:4 mode.

In your case 1:1 is preferable, in his 5:4 is.

 

[Jimbob7]

pedwar, if 3.1 is max stable with your ram @ 1:1 and you max stable overclock with 5:4 is say 3.3 onwards, its going to be faster, cpu speed is more important than ram speed.

Use ratio 5:4 and see how far that M0 will go. Then tighten the timings and enjoy the speed.

 

[pedwar]

I'm just digging out a spare HD to load up a temp OS with then I'll give it a go. I'm pretty sure this ram is a tiny bit poop tho , I've never been able to get any decent timings, GAT or PAT etc. out of it..


Surely if you bought something like this: http://www.corsairmicro.com/corsair/products/specs/twinx1024-4000pro.pdf that's guaranted to hit 250Mhz at 3-4-4-8 then it will run this at 1:1, those timings aren't too bad..

I was thinking more along the lines of their 2-2-2-5 stuff ( http://www.corsairmicro.com/corsair/products/specs/twinx1024-3200xlpro.pdf ) and losening the timings a little as this will also hit around DDR500 speeds with similar timings to above (probably identical ram with just different SPD settings)

Thanks for all the help guys, I will start messing with the 5:4 mode asap, I appreciate what you're saying about 5:4 the divider and that I will get the most from my system 'as is' (before I do any upgrades to RAM etc). (It has been a year since I've bought anything for this machine though )

 

[pedwar]

One other quick question for you guys while we're on the subject as you've all probably played with these settings a fair amount more than me.

in the ABIT Game Accelerator settings how do you have yours set? (again this was a while ago since I last messed with it all,) These seem to be the best settings I've been running for a while. If I remember correctly anything above 'Auto' on the first setting and the system won't boot. Never tried more voltage on the ram or anything.

Game Accelerator: Auto
Refresh Cycle Time: Auto
Read Delay (tRD): Auto
Read Delay Adjust (tRDA): Disabled
Command Per Clock (CPC): Disabled

That sound about right? I remember when this board first came out and they said the BIOSs unlocked PAT for 865 chipsets in 1:1 mode only or something? and that while all ABIT boards like the AI7 would have it unlocked in the BIOS you couldn't be sure that board would be able to run PAT, it was just luck of the draw (as 865s were 875s that didn't quite make the draw sometimes, or sometimes over stock of 875s if you were lucky)

Ok, that turned out not to be such a quick question after all

EDIT:

I knew there was another reason in the back of my mind somewhere of why to stay 1:1 PAT does only work at at this setting, just found this link showing the various PAT states with different settings: http://forum.abit-usa.com/showthread.php?threadid=53614&highlight=ai7

 

[larva]

865pe boards like the AI7 are not capable of PAT no matter what mode you run them in. They do have the even more effective Abit technology, GAT. Set to SR A A D D or F1 A A D D they are faster than an IC7 running full PAT in 1:1, and GAT does indeed work in the 5:4 mode.

Please, walk you fingers into the bios and TRY it rather than telling me why it won't work. If your ram is any good SR or F1 will work and the machine will get a bunch faster. If you move to 5:4 mode you can achieve 3.5GHz or more and it will get a ton faster. If you don't want to try then don't, but don't tell me it won't work; I've flailed AI7s six ways to sunday and I know what they will do.

Running Auto on the first setting is in effect disabling the GAT no matter what ratio you are running. Try turbo, then SR, then F1. If you can't run any of the three consider new ram that will allow the utilization of the GAT technology. It is indeed productive and will allow top-tier system performance without pushing the FSB and ram speeds to extremes that make everyday reliability a challenge.