Help me reach 200FSB on 8RDA+

[screw3d]

For the following specs..

Enermax EG365P-VE (350W)
Epox 8RDA+
Athlon XP 1800+ @ 180fsb x 10, 35 deg C idle, 1.65v
Corsair XMS 512MB PC3200C2 @ 7-3-3-2, 2.77v

Some helpful stuff on my BIOS:
CPU interface: Optimal,
BIOS and video cache all turned off,
No other PCI devices, all on-board stuff.

Full specs is in my sig.

I know plenty who has rock-solid systems with these specs but I still can't hit 200MHz! It will post if i change the FSB to 200Mhz and multiplier at 9, but windows XP pro won't load!

Where's the problem?

TIA.

 

[jiffylube1024]

The problem is that your chipset is maxing out - you need to do the Vdd mod to increase the voltage to the chipset to reach a 200 Mhz FSB. Do a search for "Vdd mod" on the 8RDA+ (I'm not sure how to do it myself).

 

[screw3d]

Vdd mode? ok that's something new.

but i believe some guys have their rigs up at 200Mhz FSB without doing this?

 

[Confused]

I'm sitting here at 200MHz FSB, with memory at 266MHz (66% of the FSB - crappy no name PC2100 DDR :|) and multiplier at 10.0 for 2Ghz

Of course this isn't the fastest this setup could be (due to the async, and slower RAM), but it's pretty darn fast for me!

I would get problems at 205MHz FSB, for 2050MHz, memory at 276, but the memory doesn't like it

I have just updated the BIOS, so hopefully I will be able to get the stick of 512MB Samsung PC2700 in here tomorrow from the other machine (Asus P4PE, P4 2.4@2.93), as it is currently at 405MHz, so fingers crossed it'll be good to go in my 8RDA+


Oh yeah, and I haven't done ANY mods to my 8RDA+ at all

Confused

 

[screw3d]

::update::

i m pretty sure that my RAM could run at more than 200MHz as I was running at 206 async with 175 FSB before this. As for the CPU, it's only running at 36 deg C idle, and should be able to be pushed further right?

Right now, I'm running at 185 x 10, haven't ran 3Dmark of prime95 yet, but things seem ok so far.

Pushed to 190Mhz, it even locks up Windows.

Is the northbridge the culprit?

 

[drewdogg808]

Originally posted by: marvie
Vdd mode? ok that's something new.

but i believe some guys have their rigs up at 200Mhz FSB without doing this?

it's pretty much a toss up with hitting 200fsb with the 8rda+. some of the newer boards have an a3 stepping for their northbridge and supposedly oc higher. others with the a2 (like myself) have trouble hitting 200fsb. seems the vdd is not sufficient to handle the high fsb. some people have reported better northbridge cooling to help hit 200fsb, and others have had decent success with increasing the vdd voltage to help hit higher fsb. the highest i've gotten before screen flickers/artifacts was about 194 fsb. i'm doing the vdd mod as soon as i get my resistor and grabbers....hopefully i'll hit 200fsb.

check out amdmb and aoa forums for alot of useful info.
this site is good too : 8rda.com

good luck.

 

[BD231]

Did you set your AGP to 66mhz?

 

[screw3d]

Did you set your AGP to 66mhz?

Yes I did.

185 x 10 seems to run ok... still running prime95, now at 40 deg C.

Would it help a lot if I applied AS3 to the northbridge heatsink? Is is easy to remove that heatsink?

I don't think I wanna go replacing it with an active cooling set up or do any Vdd mods..at least not yet

 

[screw3d]

it's pretty much a toss up with hitting 200fsb with the 8rda+. some of the newer boards have an a3 stepping for their northbridge and supposedly oc higher. others with the a2 (like myself) have trouble hitting 200fsb. seems the vdd is not sufficient to handle the high fsb. some people have reported better northbridge cooling to help hit 200fsb, and others have had decent success with increasing the vdd voltage to help hit higher fsb. the highest i've gotten before screen flickers/artifacts was about 194 fsb. i'm doing the vdd mod as soon as i get my resistor and grabbers....hopefully i'll hit 200fsb.

I am not sure if it's an A2 or an A3...but I think the southbridge is an A3...is this any good in indicating that the northbridge is also A3?

Been to 8RDA.com, pretty good stuff.

Anyone else who *cannot* achieve 200fsb with similiar specs?

 

[drewdogg808]

Originally posted by: marvie

it's pretty much a toss up with hitting 200fsb with the 8rda+. some of the newer boards have an a3 stepping for their northbridge and supposedly oc higher. others with the a2 (like myself) have trouble hitting 200fsb. seems the vdd is not sufficient to handle the high fsb. some people have reported better northbridge cooling to help hit 200fsb, and others have had decent success with increasing the vdd voltage to help hit higher fsb. the highest i've gotten before screen flickers/artifacts was about 194 fsb. i'm doing the vdd mod as soon as i get my resistor and grabbers....hopefully i'll hit 200fsb.

I am not sure if it's an A2 or an A3...but I think the southbridge is an A3...is this any good in indicating that the northbridge is also A3?

Been to 8RDA.com, pretty good stuff.

Anyone else who *cannot* achieve 200fsb with similiar specs?

not sure...my southbridge is also a3 (i just peeked )
but it's pretty easy removing the nb heatsink...and you'll notice just a small thermal pad, pretty pathetic. i'm sure AS3 will help alot. one thing about the nb, though...most (mine included) are slightly concave or recessed, so you may have to apply a little extra AS3 to have good contact.

 

[screw3d]

Right now my Vcore is 1.65 and my Vdimm is 2.77.

I think the Vcore doens't matter a lot as I reduce the multiplier as I raise the FSB..keeping it at about 1.8GHz.

Is it safe to bump the Vdimm up a notch without significantly reducing the RAM's lifespan?

 

[wicktron]

It's the VDD (chipset voltage) holding you back.
This is a very old perdicament that is well documented on both the Xtremesystems and AOA Forums.

 

[Pilsnerpete]

How old is your 1800+? Mine won't oc hardly at all, though I haven't upped the voltage! It may be a palomino. Are those the ones that
were out @ the beginning of last year, or was it the first Thoroughbred? Processor history's a bit tough to follow, isn't it?

I've been considering stepping to a 1700+b. My parents will get a really nice proc @1646mhz.

 

[screw3d]

Mine's definitely a TBred B, about 2 months old...but the stepping is JXXXX, which i think is inferior to the AXXXXs ?

Should've saved a few bucks and got the 1700 instead

 

[MTDEW]

1st id set the fsb to to 200mhz and use a multiplier that keeps your cpu at STOCK speed.
2nd Put ram at stock speed.
3rd Agp a 66mhz.

Then test at 200fsb to see if indeed it it is the vdd voltage holding you back. (or cooling on the NB, SB and mosfets)

4thIf you test well at 200fsb with NOTHING else overclocked, then I'd put the fsb back to stock and use the %'s to oc the ram to
see how fast and at what timings it will do.

5th Then with ram & FSB at stock, use your multiplier to find out how far and at what voltage the cpu will do.

Once you have isolated all your hardwares limits and/or weakspots, then you can start "putting it all together" for maximum performance/stability.

BTW: If you have trouble getting 200fsb stable WITHOUT OC'ing ram or cpu, be sure you have adequate cooling on NB, SB and mosfets.(?spl?)

Ive done the vdd mod on mine(A3 stepping) and to be honest, it takes a REAL steady hand (or 3hands) and a magnifying glass to be sure the solder doesnt touch unwanted places.
DON'T do it unless you understand the risks involved and are sure YOU think its worth it.

Its EASY to say its not that hard AFTER you've done it sucessfully.

But WHILE I was doing it, I was praying all the way up until my system booted..lol

 

[LastRide]

Is the 1800+ unlocked?.Your is a palomino not Tbred.I know the Tbreds are using an Nforce2 mobo.Your 1800 might not clock high enough to hit 200FSB unless you use lower multiplier like 8-9.

 

[screw3d]

Thanks MTDEW..I would try those when I have the time later. Thanks. But right now I am pretty sure that it's the m/b that's holding me back. Will apply AS3 to the northbridge later too!

Is the 1800+ unlocked?.Your is a palomino not Tbred.I know the Tbreds are using an Nforce2 mobo.Your 1800 might not clock high enough to hit 200FSB unless you use lower multiplier like 8-9.

What are you referring to?

 

[LastRide]

From what I know you have to have a Thoroughbred CPU to get all the multipliers.I am not sure if only a couple multipliers work on a Palomino CPU.The 1800+ is palomino if I am not mistaken.The multipliers will show up in the bios but don't necessarily work.The 1700+ and 2100+ people are using around here are Thoroughbred CPU's.You want to use a lower multiplier if your CPU doesn't clock high.Did you try multiplier 8 or 9 and do they work?.I hope someone can clear this up a little more.

 

[MTDEW]

I Just assumed it was a Tbred since he's using an Nforce2 mobo.
There are tbred 1800's.
link

 

[LastRide]

I guess there are Tbred 1800+'s.Only he can tell us which one he has.The palomino version or the Tbred.

 

[screw3d]

Oh sorry I forgot to put in which chip I have

It's a TBred B, the stepping starts with a J, If i remember correctly it should be JIUCB. Got it from Newegg about 2 months ago.

It now runs rock stable at 1850Mhz at 185x10 (1.650v). I had it for 185x10.5 (1.70v) for a while but it gave me blue screens

 

[LastRide]

My 8RDA+ wouldn't do 200,around 190-195.When I did the VDD mod I hit 205FSB stable,but I run it at 200FSB 11X Multiplier 2.3GHz.Your mobo might not do 200FSB without the VDD mod.Its pretty simple to do if you can solder ok.The pins you have to solder the 2 wires are a little small.If you have a small electronics soldering iron it makes it easier.Have you tried at default multiplier and how high can you get the CPU up too with 1.8-185 voltage stable with memory at relaxed timings 2.5/3/3/7 just to make it more stable?.This way you know what multiplier to use at 200FSB and you know what the limit of your CPU is.At 200FSB with 10x multiplier your at 2.0GHz.Thats what I mean to find out where the limit of your CPU is first using the default multiplier and no more than 1.85 voltage to make it stable.At 200FSB X 9 multiplier is 1800GHz and your chip can do that from what I seen I think.Try multiplier 9 at 200FSB and memory at 2.5/3/3/7 and don't go more than 1.85V if you need to go that much.Also download the latest bios March 5,2003 right here 3/5/03 top one.Some peple are getting a few FSB more out of it.If you still can't hit 200 then you need to do the VDD mod here 2 different sites. VDD Mod 1 VDD Mod 2nd link The Abit NF7-S Version 1.2 has the VDD at 1.7 Only on version 1.2 Also check out this post below yours 1800+

 

[MTDEW]

Yeah, my max "stable" fsb was about the same b4 the vdd mod, it was 194.
From what ive seen "most" 8RDA owners do need the vdd mod for 200+ fsb.
But ive seen a few who claim the got 200+fsb "out of the box".

Another thing I just thought of that you may wanna keep an eye on is I see you have an Enermax 350w psu.
Enermax and Epox combos have been known to equal a low +5v which may limit your OC'ing ability.

Just something to check also.

 

[drewski]

Originally posted by: MTDEW
Yeah, my max "stable" fsb was about the same b4 the vdd mod, it was 194.
From what ive seen "most" 8RDA owners do need the vdd mod for 200+ fsb.
But ive seen a few who claim the got 200+fsb "out of the box".

Another thing I just thought of that you may wanna keep an eye on is I see you have an Enermax 350w psu.
Enermax and Epox combos have been known to equal a low +5v which may limit your OC'ing ability.

Just something to check also.

i claim to be at 200MHz FSB with no VDD mod. i do have a blue orb on the NB & the stock heatsink on the SB.

2100+ @ 11x200MHz, 1.775 vCore (the mobo overvolts to about 1.8 or so). memory is at 4-2-2-2, vDIMM 2.77

it runs prime95 stable for over 24 hours. amazingly 201MHz will fail within an hour. haven't tried the VDD mod or upping the vCore higher. i've got no soldering skills and don't feel like getting into the 1.85 - 1.9v range w/ air-cooling.

 

[MTDEW]

drewski,
Very nice.
Wish mine woulda done that.

Out of curiousity, what is your vdd voltage at?

Mine was 1.56v b4 the mod if I remember correctly.

Do some of the boards just have a higher deafault vdd voltage?
Which would explain why some people can get 200fsb stable without a mod and others cannot.

Or is there something else that makes the difference of whether you can without modding?

I know its not the NB stepping as some have suggested it "may" be, cuz I have the supposed "better" A3 stepping.
And ive seen posts on other forums of the A2 nb stepping doing just as well as the A3, so Im not entirely convinced that the NB stepping
has anything to do with it.