• Welcome to Overclockers Forums! Join us to reply in threads, receive reduced ads, and to customize your site experience!

LanParty PRO875B how far can I go with 4 512 Geil DDR550 sticks and a 2.4c

Overclockers is supported by our readers. When you click a link to make a purchase, we may earn a commission. Learn More.

robertway

Registered
Joined
Aug 31, 2004
Hey folks, I'm a newbie here in regard to posting but have been a reader for a month or so now, please excuse the long post but I wanted to give a history of what got me here to ask questions. I have just gotten myself the LanParty Pro875B board (04/09/2004 Canterwood) as well as 4 sticks of Geil Ultra Platinum PC4400 550MHz RAM and a 2.4c. I'm running everything under a 1/2" Water Cooled system with a DangerDen Maze 3 on the CPU and a DD Z-Chip block on the North Bridge. Sitting idle with the 2.4c @ default 200FSB I'm idling at 19C, about 1C above ambient in the room I'm in.

Now I do not claim to be ANY kind of OC wizard, but from all my reading and some previous OC work with an AMD 2500+ (sorry for mentioning the "A" word around here :beer: ) I have some basic knowledge about how to proceed but when I start to hit a barrier I kinda get lost. By the way the 2500+ was a pain if I may add since I was running Corsair PC3200 XMS memory on a Gigabyte board, another story though, anyway...

My expectations were to be able to run the Geil at its "rated" speed by setting the FSB to 275 with the ratio @ 1:1. Now I didn't do that straight away as I wanted to ease the system into the higher speeds so I started things with 225 on the FSB for a 2.7GHz and DDR450, well below what these components are capable of. Let everything run overnight with a burn-in using SiSoft Sandra 2004 and woke in the morning to find everythin fine. Running about 21-22C during the burn-in.

Next I went right to 250 on the FSB for a 3.0 and DDR500, this time I had to start bumping the voltage up on the CPU and DIMMs, going to 1.575 on the CPU and 2.7 on the DIMMs. I was able to get a full night's burn-in without any problems. Running at load at 23-24C

From here I was going to go in much smaller jumps, +3MHz on the FSB until I hit a limit. Well with the first 3MHz jump I hit a limit and XP would BSD during the initial boot screen. I tried playing with more voltage to the DIMMs and/or CPU to no avail, I finally lost track of where I was and backed down to start my ramp up again. I even tried manually setting all the DIMM parameters by disabling the system bandwidth and setting the DIMMs at 3,8,4,4 which is what they're spec'd at, the MB had them at 2.5,8,4,4. Still to no avail beyond the 250 FSB barrier.

I opted to see if I could push the CPU more by backing the DIMM Ratio to 5:4 setting and running the FSB @ 275. This gave me a 3.3 on the CPU and DDR440 on the DIMMs. I put 1.575 to the proc and 2.7 to the DIMMs and when I left the house for work this morning (which I'm at while I type this) it was over an hour into a burn-in with the CPU at 24C steady.

My real concern here is the memory, I believe the CPU can do more, it is only 24C at 3.3 which is nothing to frown at as some folks are doing that on air at 39-45C under load. Am I holding myself back because I'm using 4 sticks of mem, I have read some posts that it burdens the mem bus too much with 4 sticks. If I have to run the 5:4 ratio to get the CPU higher, so be it, I need 2 gigs of mem for the Photoshop work I do but would also like to see how far I can push the system using maybe 2 sticks since I have seen the Geils pushed to about 287MHz in several reviews.

Anyinsight into what mem settings would help me, especially the best way to determine the right voltage to send to things.

-------------------Update----------------------

Poking around a bit more after I just posted this I found in the Mem Forums that some folks spoke to Geil and they say that in order to achieve the spec'd operation of their PC4200/4400 sticks you need to run em' at 2.9v which I haven't tried yet, so that is one piece of information I can add to my arsenal....

----------------Another Update---------------------
OK, got a bit further, I bumped the vDIMM up to 2.9 and the vCore to 1.65, using the 5:4 ratio and 285FSB I was able to get a full 12 hours in of a SiSoft sandra burn-in of the CPU with a stable temp of 27C. Proc at 3.4 and memory at 454MHz. The downside is I tried to run Prime95 and the thing craps out immediately giving me a rounding error. Booting from a CD and running memtest86 I get all kinds of errors in test #3. In light of this I have reset the system back to defaults for the 2.4c running @ FSB200 and 1:1, put the vDIMM at 2.9 and am going to begin pushing the FSB incrementally and running memtest to see where things get funky. I'll also be pulling out 2 of the 4 sticks of Geil to see where that gets me and find out if the 4 sticks together are holding me back. The only other odd thing is I have been setting the mem manually at 3,8,4,4 but CPU-Z and SiSoft are still reporting it as 2.5,8,4,4, don't know if that means anything at this point. I really need to educate myself about loose and tight timings as I don't even pretend to understand them at this point. When I left the house this morning, memtest was running so I'll see how it fared when I get home this afternoon.

As always, other feedback from folks is always greatly appreciated.

Thanks in advance,

Robert
 
Last edited:
OK, seeing how I'm being forced to figure things out on my own here, which is actually the best way to learn sometimes, I'm zeroing in on a possible culprit to my situation. I have noticed that my 3.3v rail is reporting in MBM5 as 3.2v while idle and falls to as low as 3.15 under load. With the Geil DIMMs needing 2.9v, at least, to run at theor DDR550 spec, assuming the rail readout is correct this may be my problem. Even when I set the vCore to like 1.65 it reads as low as 1.58 under load. I'm going to be picking up a multimeter today to get a true reading of the rails. I'm running an Antec TruePower 550 which I know to be a well respected PSU but there is always the chance that alemon makes it off the line every now and then.

Keep the lack of responses coming... it is making me think for myself :) (ignore the sarcasm... just venting...)
 
Nevermind the suspect 3.3 rail, I put a multimeter on it and it is reading 3.31 at the motherboard and 3.30 under Prime95 load. It even measures 3.34/3.33 at the aux connector. Is it possible that the board is dropping the ball handling the 3.3 incoming. The Geils I'm using are power hungry and require 2.9 to run spec so I'm afraid the board isn't really pumping the 2.9 into them that I have it set at.
 
Back