First off, thanks for everyone who shared their mods as well as tips/advice.
Well, after 2 days of running stable on stock fsb and all, I decided to take the plunge and mod my E5200 to 266Mhz using the BSEL and VID mods done by many here.
I started with a VCore of 1.225v. Looks like I have less oc headroom as my vcore is already up high in the range. Was able to push fsb to 230Mhz via the BIOS but didn't proceed any further as that will drive my DDR1 to more than 15% than it's rated speed. At 230 though, it's already leaps and bounds beyond my previous setup so I was already happy but was I .......... ????
Reviewed the Intel specs for the E5000 series core2duo (thanks Ileader36 for the link and pics and the mod steps) and figured out which needs to be set from 0->1 and vice versa. I like to just go a hair below Intel's max vcore per spec so went with 1.3375 which turned out to be grounding both VID1 and VID4 to VSS. Of course BSEL1 -> VSS for the BSEL mod.
So last night, I decided to shut everything down, pull the E5200 and start the BSEL and VID mods. Got the rear defogger kit from Pepboys. Staring at the cpu, I was like, how in the world am I going to see what I'm doing. Looked for a magnifying glass but no go. Then I just realized, I have a high-def camcorder that I can hook up to my 42" plasma and zoom right in so I can see the pins really well, add some lighting too. It turned out to be awesome!!!
It took me 3 tries to get the defogger solution to stick where I want it to. First try was with meticulously applied low-tack blue painter's tape. Solution came off with the tape Second try was without the tape and used toothpick. Well it worked for the most part but I ended up with a pool of solution on one pin which then smeared into the adjacent pins. Remove and start over again. Third try was with a needle which I stole from my wife's sewing kit . This one worked this time. Almost too little solution most of the time but never too much as the pin can only hold enough. I also needed to make sure I don't scratch those tiny little dots on the cpu or the board itself.
While waiting for it to dry, I took out my old Zalman CNPS7000-Cu cooler for my S478 and bought the 775 adapter for it and mounted on the board. Only thing I don't like with the CNPS is that it's not a PWM fan so board can't control the speed. But since I'm overclocking and raising the vcore, I figure it would be good to run it at full-speed 100% of the time and besides, it's not that noisy.
Put everything back together, plug everything back in, pushed the Power switch while praying and VOILA!!! I got 1066 FSB and cpu is running at 3325Mhz with a Vcore of 1.3375v. What a sigh of relief - this was my first attempt at modding a cpu. Booted into Windows and ran Orthos right away. Did other benchmarks and they were definitely up from stock. Played COD5 and no glitches whatsoever. Temps were good too hovering only up to 53-54C max when loaded and stayed at 35-37C idle. When Orthos was running, it hit 58C at one point but didn't stay there long.
Memory stayed at DDR400 spec as Ileader36 said so components are happy. Ran Orthos overnight for 10hrs and not a minor hiccup. Then I thought, hmm, why not up it to 290Mhz and see what happens. Well it booted up to XP but Orthos keep failing right away. So I decided to keep it at 266.
Here's some screenies that I took:
CPU-Z
CPU-Z Memory
CoreTemp
Hardware Monitor
3dmark06
3dmark 05