Epox 4PEA+ and "AGP" Voltage.

Just so you all know the item labelled as AGP voltage in bios is actually the chipset voltage. Raising this to 1.8v from the 1.5v stock will give you a considerable boost in memory speed.

Figured this out last night and it took me from DDR472 100% stable in windows to DDR485 100% stable in windows.

I believe its labelled AGP voltage as its altering the northbridge (AGP and MEM controller) voltage. Well its the only rational explanation I could come up with.

Anything above 1.8v makes little or no difference for me. The heat output of the northbridge is substantially higher. Im using an IT7 northbridge heatsink with the Epox 40mm fan. The base of the heatsink is pretty warm, but nothing to worry about.

PiLsY.

So Pilsy, do you mean you have to up BOTH the VAGP and VDIMM for max performance on your DDR?

I am testing a 4PEA+ now and yes, it is unholy at running DDR. My PX845PEV PRO does DDR456, 2-2-3-6, but I can run the same stick at DDR454, 2-2-2-5 on the Epox, but needs 2.9 volts to clean out Memtest. Unbuffered Sandra memory scores are 1950-ish. I'm stable in all 3D and SuperPI. I need a better CPU (171+) to go higher on the DDR (running 1-512 MB XMS3500 C2).

My notes on the 4PEA+:

1. The BD7II and Alb. board beat it by 1 mhz on the same CPU, with same VCORE. I need a bit more VCORE on the Epox to gain the 1 mhz back.

2. If you install a 250ZIP drive and have a cartridge installed when you boot, the contents will be assigned your D: drive. Not too cool for your shortcuts. So I just make sure the drive isn't inserted.

3. The 4PEA+ is not as fast in DOS as the Alb board. The latter is 3-5X faster formatting and partitioning drives.

4. At DDR454, 2-2-2-5 it takes 5'56" to run a Memtest loop. At DDR456, 2-2-3-6 it takes 6'13". But the Alb board seems faster overall. It takes 50 sec to boot Win98SE fully on the Epox. I will test the Alb next time I install it, but it booted in about half the time. A ZIP drive really slows the boot time on a lot of boards.

But the 4PEA+ has no hot restart problem like the Alb on extreme overclocks, and the Alb only goes to 2.8 VDIMM. I got my 4PEA+ in Japan and both it and the Alb have 3:4 and 4:5 in the BIOS on 'b' CPUs.

Mmmmmm if you raise the AGP voltage/Chipset voltage is it only raising the chipset voltage? Or does it also raise the AGP voltage like it claims?
Ill give it a go on my 4PEA+ when i install the MCX4000

I needed 1.8v chipset at first, but after 48 hours or so of bedding in its now stable using 1.6v, so even if it does up your AGP voltage somewhere along the line its damn close to spec anyway.

The difference seems to come in that without the AGP voltage up you cant really take advantage of the 3.0v and higher vdimm. It makes little difference. With the "AGP" voltage a touch higher you start seeing good returns for the extra voltage on vdimm.

Its given me an extra 100mb/s unbuffered stable day to day - not something to turn your nose up at.

Am now looking for a 19 or higher multiplier P4 thatll run 183mhz FSB (day to day stable limit).

The board does have high FSB boot issues, but only at 185mhz plus. Set FSB sorts that out if you can go any higher.

My board neds the JCLK1 mod to get 4:5 in bios using an "A" cpu. I dont have both 3:4 and 4:5 available.

PiLsY.

Either the 4PEA+ is not putting out proper voltage to the video card or my 9700 Pro Rev. 1.0 has regulator problems, as I notice at default AGP voltage I can only run the card at 360/324 when it runs 360/345 on Asus boards. However, by boosting the VAGP to 1.8 I find I can get the memory up to 340. I think the card is the problem.

I got a 2.40b C1 over the weekend and it will do around 3.2 gig so I was able to test up to 177 fsb. At 3.0 VDIMM I was able to run 3:4, DDR472, 2-2-2-5, on a 512 MB stick of Corsair! Totally clean in Memtest. Hit 17,266 on 3DMark2001, with the slow DirectX 9.0 drivers and no tweaks. SuperPI failed though, but have to check again, maybe with lower VAGP.

Man, these C1s are amazing; I was able to run 3 gig at default voltage, which is around 1.50 true on this board! Even checked out clean in Memtest and SuperPI. Needs around 1.58 volts for 3.1 gig and runs out of gas around 1.71 volts, for 3.2 gig.

The 4PEA+ does seem to have a minor cold boot problem, a la the BD7II: on first boot every day screen stays blank. Have to press the restart switch to get the screen to pop up. Must be the 6-layer PCB like the Abit boards.

I think a lot of these problems with the board can be solved with BIOS updates. 'Cept for the Albatron, don't think there's any other DDR board out there that can touch its memory scores. Problem with DDR is, running absolute fastest CAS is crucial to performance. Once you've tasted 2-2-2-5, hard to go back. Lose around 200-250 3DMark points going from 2-2-3-6 to 2-2-2-5, or 75-90 unbuffered mem marks from 2-2-2-6 to 2-2-2-5.

I really want to get one of those 2.4's. My 1.8A just doesn't cut it for me, and I need 1.85V to get it stable at 2.4 which is too much for me when it's only aircooled atm.

My PC3500 needs to be put to work properly.

And mine has the same Cold Boot problems. No really biggie though seeing as I leave it running all night anyway :)

worst 1.8 C1 ever.


http://146.teambota.com/bench2.jpg

http://146.teambota.com/bench1.jpg

I want one of them :(

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1. The BD7II and Alb. board beat it by 1 mhz on the same CPU, with same VCORE. I need a bit more VCORE on the Epox to gain the 1 mhz back.

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I was able to gain the 1 mhz back by upping the VAGP to 1.8, so now the 4PEA+ matches the other boards at same VCORE.

This board will run Corsair XMS3500 C2 at uncharted territory. At 2.9 VDIMM, I was able to max out at DDR466, 2-2-2-5! This is a 512 MB stick.

What's great about this board is the spacious layout so easy to change DDR without removing the video card. I'm going to be testing a Kingmax PC2700 with 6-ns Winbond soon. Also an old Samsung DTL stick that maxed out at DDR412, 2.5-3-3-7 on a P4B266-E. The Alb. board took it all the way to DDR456, same lame settings, but unbuffered mem scores were 1850! The Alb. board would not run this stick at anything but CAS2.5.

anyone have noticed if that board have and FSB phisical limit???

seems that IT7 MAX2 V2.0 stops around at 197-198mhz, both mine and hipro5 boards have this limit.... so i want to change my it7 but need a mobo that can do fsb highter than 200mhz... know one that can do that??

Well the FSB is limited in bios to 200mhz, and ive managed to load into windows at that. Stability appears to be very flaky above 193 - 194mhz though.

Really need a vdimm mod for this board. 3.4 - 3.5v would be ideal. 3dmark is doing the classic "not enough memory voltage" drop to desktop at between 485 and 490 on the memory.

PiLsY.

is this AGP voltage discovery for all 845PE boards as well ?

I got my 2.4 today and it was benching 3dmark at 175 and couldnt even boot into windows at 180 cos of BSOD and then I thought Id try this trick and now Im ssandra mem benching at 180 @ 2-7-2-2 @ 3.05vdimm :D

3704/3704

You are awesome Pilsy :toast:

Screenies to come, still testing

[Edit: chipset voltage needed to be bumped vagp/chipset to 1.90 for 180fsb to run 3dmark stable and i got 19097.......i then tried 185fsb and it rebooted half way during sandra test so i thought §§§§ it ill bump vagp/chipset to 2.0 and then booted again and it ran sandra scoring me 3810/3810...(sorry Pilsy and macci, no unbuffered, I only just remembered, and pc is shut down now)

I tried 3dmark but rebooted as soon as i clicked benchmark :D all is at 3.24vdimm...ram isnt even hot :) Does anyone recommend anything to get it to run 185 for 3dmark?

DDR493 @ 2-7-2-2 @ 3.24vdimm.....This is the best damn 512meg xms3500 in the world :p hehehehe Im going to do more memtest etc tomorrow, I was just interested in the ocing tonight. The cpu is a 2.4b C1 SL6EF 20/11 :)

just like mine creative...

what are you using to cool him? Vapochill? i use mine at 180 but with a normal MCX4000.

ps: used, my epox died... the firewire chip just burned... grrr...

Creative - try TRAS 7. NO appreciable performance drop, but ive noticed that on boot up every now and then I get a registry restore unless the TRAS is set to 7.

How hot is your northbridge getting? Try and touch the edge of the base of it to get an idea. If you have an IT7 northbridge cooler around it goes straight on, and with a little bending of fins the epox fan screws into it too. Helps loads at keeping the temp down.

PiLsY.

Raptor, yep shes cool in a Vapo :) Very nice sticks of ram we must have :D

Pilsy; TRAS 7 has been being used pretty much the whole time. This morning doesnt look like it will get much better than lastnight. 185 2-7-2-2 boots into windows and lets me do sandra and some PiFast but not SuperPI.....Wierd.

The NB, I must admit I havnt really checked it. Im using a TT Tiger on there and it seems to be doing OK. Default I had passive cooling with some Silver EPox HS and it actually looked OK, but I took it off asap. Maybe put it back on and use the fan from the Tiger?

On a sidenote, does anyone know why after installing a Swiftech MCW50-T, that I can only clock my mem to 350 now instead of the usual 380??!!! :(:( Its causing me about 400 points in 3dmark :(

To Pilsy and macci:

You guys have measured the AGP and chipset voltages right ? I have a few questions regarding this thing.........Is "AGP Voltage" in the BIOS just a mislabelled "Chipset voltage" or do those two share the same voltage regulator (which means they both increase ?) ?

They both seem to run off the same mosfet, BUT....

AGP voltage adjustability does not alter the voltage to your graphics card at all. Your graphics card pulls its power through the AGP slot, and then converts it to the relevant voltage (3.3v for agp 2x, 1.5v for agp 4x and 0.8v for agp 8x). All increasing your agp voltage does is increase the power going into the agp slot, after which your card converts it to the relevant value. By upping the vAGP you ensure that your card always receives the full 1.5v from its power circuits.

In explanation - vAGP of 1.5v supplies a direct 1.5v to your card. Normal pulses in current occur, and the card has to simply let the value the mobo is supplying run through its power circuits. Say your mobo is supplying between 1.45 and 1.52v (as you know voltages go up and down, theyre never really constant). This means your card is getting between 1.45 and 1.5v from its power regulator. If you up vAGP to 1.8v then your mobo will supply say 1.75 to 1.82v from the agp slot. Your card will then pull down this value to 1.5v. As the AGP voltage is always above 1.5v from the mobo side, your card will always pull it down to 1.5v and you have a constant(ish) internal current. It wont do the power regulation on your card any harm as its designed to be backwards compatible to AGP 2x (and therefore 3.3v) so youre well within its upper voltage range.

PiLsY.

very cool finding Pilsy, I will have to check this out as my main gripe with my PEA is memory speeds

How do you mean Darius? The 4PEA is an excellent clocking motherboard anyway - this just helps you push the envelope a bit further.

What memory and voltage are you using and what speed are you stuck at? Dont bother adjusting timings as they make no difference to FSB on this board. 2/5/2/2 gets me just as high as 2.5/7/3/3.

PiLsY.

Edit

why i can´t pass the 154fsb?
i have the 2.66cpu, cooled by a volcano 7+ mod...
its the volcano the problem?
i did what you said PiLsY, about the agp volt.i put on 1.8vol.
the mems are 3.2vol., and the cpu....well it depends, sometimes 1.750,other 1.85
i notice that if i put too high, it don´t works
:mad:
im thinking that i waist a lot of money:(
oh, and my mem are ocz el 3500 (256*2):D
maybe....just maybe with a promy, i will resolve the probem:rolleyes:
imagine me when i see yours posts....185fsb and so on:(
you having problems at 198 fsb.....and me:( :( :( its not fair:slobber:
help...please:D

What can I say- i've been reading these threads with a grain of salt----
I bought one of these boards in November and it puked when left to burn in overnight. I was running my IT7 max2 ver2 with my 2.4 @182 fsb 4:5 ratio enabled, around 452 mem speed, with a stick of XMS3500, @ 2,7,3,3. 3:4 was a no go at 174 fsb and up on this or any of the IT7's I've owned. I bought another Epox 4PEA+ last week, and this thing rocks- you guys are right.
Burning in a SL6D6 2.26 @ 181 fsb, 3:4 ratio, 474 mem speed.
And agressive timings to boot!! 2,6,2,2. Nothing fantastic, but not bad with a 512 stick.
This Epox beats the snot out of any of the IT versions I've owned.
I also have both 3:4 and 4:5 ratios available, and my board came with the 12/04/02 bios installed.;)
Now I know the comparision is with 2 diffrenet cpus, in 2 different systems, i'm just amazed at how much more the Epox would take this particular stick of ram.

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oh, and my mem are ocz el 3500 (256*2)

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That is a problem. OCing x2 sticks is always very hard.

use only one stick. or sell those 2 and buy one 512MB!

its not the same, if i use only one of 256?
i did that and i had the same results....:(

Bah clicked reply instead of new thread....

:with:

sorry...about that:D
but i still have the same problem:(

Have you tried with memory at 1:1 to see if its the OCZ holding your o/c back?

PiLsY.

yes!
i can anchieve 157fsb:)
but after enter the s.o., he freezes:confused: :(
i think it´s the volcano....probably not good enought, or the cpu:mad: