Interesting. My first bet would be a BIOS problem. 3.06 GHz sounds like a Northwood P4 with HyperThreading, no less. These were introduced in 2002, so your 2004 BIOS should be OK. However, it is possible IBM never included support for these latest chips for your mobo (could be various reasons). Do a little digging, make sure it's compatible.
If it is, I'd start by removing your CMOS battery for a minute or two, to make sure your BIOS goes completely stock. If that doesn't help, re-slot your older Pentium, head into BIOS and disable HT, vmem support, and maybe drop the memory clocks, if the BIOS even allows it. Then retry the newer Pentium.
Oh, and if you have a way of doing that- make sure the chip isn't faulty. It would be best to drop it into a mobo that you KNOW will work (or already does) with it, if you have a friend or colleague running one.
Welcome to Tom's Hardware Forums,
What processor did you get to replace the original? Does the motherboard support that processor? Just because it physically fits does not mean it'll work. 2GHz to 3GHz is quite a jump for a motherboard. Looking through Lenovo's* website for the Netvista 6794, I could only find information about P4 processors up to 2GHz, nothing faster.
*Lenovo took over IBM's consumer PC division almost 10 years ago and provides some support for IBM products
I just updated the CPU in my Netvista 6794. The MB on this PC only has support for 400 MHz FSB. The fastest CPU Intel made using a 400 MHz FSB was 2.8 Ghz. I found one on ebay from a gentleman in China for $9.99 USD. Received it in about 5 days. It provided a noticeable improvement in speed for very little cash. My daughter uses this PC to play Minecraft and Spore and the upgrade, along with a $40 GeForce AGP card provided her with all the speed she needs to play these games without lag. The key is to find a CPU that is marked 2.8 GHz 512/400. 512 is cache. 400 is FSB. I believe the production number for these processors is SL7EY. If you still have the PC and want to upgrade at all you can search with Pentium 4 and this production number to find these. The only issue I have had is when booting I get an "Error:0167 No processor bios update found". This seems to be that the bios doesn't recognize the CPUID 0F29. But since they only made these models for up to 2.2 GHz, a bios update would most likely not solve this issue. But the BIOS recognizes the multiplier and everything shows as a P4 2.8Ghz so I don't really see a need to worry over this. Both the 1.8 GHz CPU and the 2.8 GHz CPU run in the same Voltage range and have the same core, just sped up. Hope this helps
OH, the 3.06 GHz P4 has a 533 FSB and uses Hyper-Threading. I am assuming the Hyper-Threading is your problem as the bus speed would just mean the CPU would run run at 2.3 GHz with the multiplier being 5.75.
The only problem I had was the 0167 Error No Processor BIOS update. I had originally found the lenovo webpage showing all the models built for the 6794 and the fastest processor was a 2.4 GHz P4. I assumed this meant they hadn't added support for the 2.8MHz to the BIOS. I decided to investigate further and found that the BIOS update instructions included all the revs for the BIOS. Sure enough, they had added the D1 stepping and the F29 processor ID support. So, after downloading the BIOS update that runs in XP(or whatever OS you use), I followed the instructions and the new bios recognizes the CPU and everyone is happy.