video display errors after 209FSB

[ayankdownunder]

Hi I need a suggestion. I have tried EVERY combonation of voltage setting, ram timings and clock speeds to resolve this problem to no end!! I am trying to get past 208FSB. anything after that results in bery bad display problems. I get blue screens with NV4 display errors or a screen that flashes black and then gets corrupt and then crashes. The machine itself seems to boot fine and will pass 3dmark 01 and 03 up to 208FSB but 1mhz more and it dies. I have done the VDD mod and I ahve tried voltages from 1.7-2.05 with no luck. I have the most current BOIS and I have made sure that I lower my ram timings but it does not make sense!! I am getting great results with a 2400+ at 10x207 at 1.80V at 43C with ram timings of 2-2-2-5. 1mhz after this kill the video. I just dont understand. I have even tried the spread spectrum setting with no luck. Have I capped out my overclockability?? or is something else holding me back? Has anyone had this problem?

Cheers,
Nick

[ayankdownunder]

Yes the AGP is set at 66mhz.

Thanks,
nick

[Iron_Dreamer]

I have the same problem, anything over 208 FSB gives me screens flashes and eventual BSOD's, anything over 200 is not rock-stable, but I can run 200 for weeks on end (no additional cooling or VDD mod).

[ayankdownunder]

I am sure that others have had the same problem. I hope that they will post their experiences. What video card are yo using?
I am using a Geforce 3 Ti200. It is overclocked but I get the same problems when I set it to default settings. I am happy with my current performance but I would like to know what is the cause of my "problem".

Thanks for replying,
Nick:beer:

[raven_swe]

I see this problem at 205+ fsb.... have no idea why ...

I have not tried to increase the agp voltage... but i doubt it will help...

edit 10:13
tried now to increase to agp voltage to 1.6v
and so far running prime...
Better but still the same problem...

[Iron_Dreamer]

gainward gf3

[ayankdownunder]

Has anyone else seen this issue with other video cards???? GF4, GF2, ATI etc????

[ayankdownunder]

EPOX TECH,

Does the 66mhz AGP lock work after 200mhz fsb?

What could be causing these problems with video after 209FSB?

Thanks,
Nick

[Walrusbonzo]

I'm starting to think there is a NForce2(Epox 8RDA+) NB/AGP and GF3 issue. I have a Hercules GF3 Ti200 64mb. Both RAM and Core cooled well. The motherboard has VDD mod so my VDD is at 1.79v, NB is cooled with massive 80x60x30 HS with a 2000rpm 80mm fan. SB, CPU MOSFETs and VReg chips are all fitted with heatsinks.

My Epox 8RDA+ ALSO has problems with FSB over 208MHz! This is with AGP at 66MHz, I'll get screen corruptions as you lot are. AGP voltage doesn't help at all.

And being the overclocker I am I decided last week that I was gonna volt mod my GF3. I was previously stable with the core at 230Mhz and RAM at 480MHz, this was disappointing as the RAM is supposed to be rated for 500MHz according to Hercules's website. VAGP didn't help my overclock either. So I modded the VCore and VMem of the card. My new stable(and no artifacts) clocks were 220MHz and 530Mhz.

So I gained on my RAM, but lost out on Core, even though voltage was higher VAGP helped nothing at all.

So I undid the VCore mod and I was able to get 230MHz stable again. I then thought I'd try LOWERING the AGP frequency to 50MHz.

I was then stable with my GFX card at 250/530, so I gained 20MHz on my GFX core by lowering AGP frequency.

All this points to me as being some sort of NB/AGP/Power issue, and probably only for power hungry cards that draw power over the AGP. I have a feeling that Radeon 9500/9700 users are probably getting higher FSBs.

Lowering AGP frequency to 50MHz doesn't help me to increase FSB or stop screen flicker. But I believe there is an issue here. Maybe some GFX cards are drawing too much power over the AGP, which is effecting the voltages to the NB. I know I saw somewhere a Epox tech saying that the NB and AGP voltages were linked somehow, he said doing VDD mod also does something to AGP voltages. Problem could lie here??

Anyone else got any thoughts on this?

[ayankdownunder]

Sounds like you may have the answer. I have EVERYTHING cooled as well and am getting the EXACT problem you are. WHat can we do about this? I have a ANTEC 480W PSU and I would hope anything with a rated power of 400 or more should handle this without issue. My Server has an HEC 400W and it has Dual 1900+ CPU's and 6, U160 SCSI3 10k RPM hard drives. Point being that our PSU's should be doing the job. If it is a power issue I feel like there is not much we can do .

Do you know if the AGP lock at 66mhz is effective after 200FSB? If not could a BIOS revision "correct" this?

[Walrusbonzo]

I just remembered some more.

When my GF3 was NOT Vmodded, clocks were at default of 174/400, and FSB was at 200MHz~ if I raised the AGP frequency even to just 70MHz 3DMark 2001 would lock also, just like if AGP was at 66MHz and the card was overclocked.

I think I'm gonna try lowering FSB, lowering my GF3s clocks, upping AGP frequency and see if I still have the problem.

I'm gonna trey my TNT2 out my other system, see what effects it has. I have an AGP Voodoo 3 around here as well, I'll try that.

Edit: Note I have a Enermax 550w PSU, a very well cooled system, and NO PCI cards. I also only have 1 HD and 1 DVD drive installed in my main rig. So it's quite a bare system.

EDIT: PLEASE, anyone with an Epox 8RDA+ and a GF3 come forward. Tell us your FSB, AGP frequency, AGPvoltage, VDD mod? GFX card vmods? GFX card Overclocks? We can perhaps locate the problem easier if you do.

[Walrusbonzo]

I have some VERY interesting news for you all!

I swapped over the two GFX cards in the 2 systems in my sig and have had results as expected.

I can clock the FSB MUCH higher with my TNT than my GF3! With my GF3 installed 207MHz was the highest stable FSB I could get, 212MHz was about the highest it would boot. At 208MHz I'd get screen corruption and WinAMP would stop playing if I was Prime95ing.

However, I can now get it to boot to Windows at nearly 225MHz, DUAL CHANNEL! I even managed to bench the system at 220Mhz.
http://crosontech.dns2go.com/pictures/proof.jpg. Memory timings were 10,4,4,2.5 for stability reasons.

217Mhz was about the highest I could SuperPi without screen artifacts, 10Mhz higher than before!

So why is this happening? Well to me it's obvious, the AGP bus and chipset SHARE their power source, and I think Epoxc techs will confirm this. I'm 100% certain one of them said doing VDD mod affects AGP too.


Now, another interesting point to back up my findings. I put the GF3 into my MSI system which it used to be in before I got this Epox board. Windows would get so far booting and would CRASH, HARD. Now the MSI 745 Ultra isn't even specced for 166MHz FSB, that's overclocking, and while this is stable with the TNT2 my Gf3 hated it. Backing off to 133Mhz allowed me to get into Windows.

It should also be noted that several months ago I posted about a problem with my GF3 Ti200 overclocking and FSB speeds on my MSI 745 Ultra on OCWorkbench.com. There were others with GF3s and GF4s that ALSO had the problem of the computer locking when FSB was 166MHz or higher and playing games/running 3DMark. Again, on that board, the AGP and Chipset share power, Speed J and Pegasus can testify this after Speed J's GFX card had burn marks on the AGP connector after doing Chipset mod on the motherboard.

Speedy J Burning his AGP slot - http://www.ocworkbench.com/ocwbcgi/u...;f=21;t=000486

Me being disgruntled that my GF3 doesn't like 166MHz FSB even though AGP is at 66MHz - http://www.ocworkbench.com/ocwbcgi/u...;f=21;t=000671

Note that a few others had problems with their GF3s! It seems that GF3s do not like high FSB even if AGP is in spec.

I also did Chipset v mod on my MSI 745 Ultra, that reduced my GFX Card OCing potential, chipset V Mod on the Epx 8RDA+ will probably do the same.

Around the same time I built a system for my friend, I got him a Radeon 9700 Pro, and me being curious about the GFX cards power sourcing decided to try it in my machine. It would run 3DMark fine for hours on end with the FSB as high as 172MHz, obviously the fact that the card was drawing it's power from the PSU and not over the AGP bus helped.

Has anyone else noticed these things I have?

[ayankdownunder]

WOW!!!! That is some in-depth research in a short period of time. Thanks!!!!

I guess the next thing we need to do is find out if Epox Tech can provide us with some information regarding a "cure" to this problem.

At this point do you feel that the ATi cards use alot less power than the GeForce series?

I wonder if these guys getting 250mhz FSB's are using for video?

I think I may go and do some research.

Last question.

Do you think that a new revision of the board could provide the needed changes for us? If Epox is supposedly going to offer a new revision allowing VDD voltage mods wouldn't they have to consider the AGP problems that we are having?

Your time and effort is MUCH appreciated:beer:

--Nick

[MasterAtArms]

Holst said on xxtreme forums that the source of the failure when (over)doing the Vdd mod was not theNB itself but its power regulation. The new nForce2 Epox will have adjustable Vdd and will have different power regulation for the NB.

[raven_swe]

nice info guys..
but the one thing i am wondering about is 200fsb+ and agp frequency... is it locked to 66mhz after 200fsb?

[Walrusbonzo]

ayankdownunder: No I don't think ATi cards use less power than NVidia ones, but the 9700 and 9500 draw power from the PSU directly, not over the AGP bus. Therefore not stressing the motherboards power regulators, which it seems the AGP bus and NB share.

The reason I think this is because by putting my wimpy TNT2 in instead of my power hungry, overclock and vmodded GF3 I was able to get higher FSB.

To prove that my GF3 is a lot more hungry than my TNT2 I put the GF3 in my MSI 745 Ultra, a board that uses power regulation that's ALSO shared by AGP bus and NB. This made my computer crash on bootup UNTIL I dropped the FSB!

ALSO, I tried my m8s Radeon 9700 in my MSI board, and it was perfectly stable at FSBs upto 172MHz.

REMEMBER, the 9700/9500 DO NOT draw power over the AGP bus, but directly from the PSU

I.E. To get the highest possible FSB on YOUR board, then use a GFX card that draws power from the PSU....

PLEASE NOTE, I am not saying that using a Radeon 9700 is going to guarantee you get over 200MHz FSB. But with everything thing else the same, a Radeon 9700 will let you get higher FSB than any other GFX card that draws power over the AGP bus. Understand?

I'm 99% sure the AGP frequency is LOCKED at what ever you set it to, regardless of the FSB you use.

[Walrusbonzo]

Originally posted by MasterAtArms
Holst said on xxtreme forums that the source of the failure when (over)doing the Vdd mod was not theNB itself but its power regulation. The new nForce2 Epox will have adjustable Vdd and will have different power regulation for the NB.

All being well, this NEW power regulation means the AGP and Chipset have their own.

[Stepper]

Not that I even have a clue...however...on my system...both the AGP slot and 5 other items share the same IRQ...the PCI bus...NVIDIA nForce2 AGP Host to PCI Bridge...AGP Card also share the same memory range as well...

2k and XP cannot rebalance resources in the same way that 98 does. After PCI resources are set, they generally can't be changed...

I would think that if the AGP slot could have it's own IRQ & memory range...some improvement may be gained...but then again...I don't have a clue...

[Walrusbonzo]

You just keep saying that to yourself

You don't have a clue, IRQs are not the problem here.

It's purely a power issue with the NB, AGP bus and certain GFX cards.

[Stepper]

How Rude!...believe me...It won't happen again!