Warning: main(php/nav/nav2.php) [function.main]: failed to open stream: No such file or directory in /home/pcx4010/public_html/p4oc.php on line 22
Warning: main(php/nav/nav2.php) [function.main]: failed to open stream: No such file or directory in /home/pcx4010/public_html/p4oc.php on line 22
Warning: main() [function.include]: Failed opening 'php/nav/nav2.php' for inclusion (include_path='.:/usr/lib/php:/usr/local/lib/php') in /home/pcx4010/public_html/p4oc.php on line 22
Article Date: June 22, 2002
Updated: July 29, 2002
Written by: Dwayne Sessom
Absolutely NOT Sponsored by: Intel Corp.
I'm sure by now, most of you have heard about the overclockability of the Pentium4 Northwood.
Namely, the 1.6A Northwood. Many have posed the question "Is the 1.6A the next Celeron300A?". I'm here to tell you, this CPU is better. Way better. It is the best price-for-performance processor ever made. Period. This CPU now retails for somewhere in the neighborhood of $140USD, and I managed to get it to 2.4Ghz right out of the box. No modification, no special thermal compound, no special fans.
I only used what came in the box.
Even though the CPU did run at 2.4Ghz, the highest vcore setting I had on this motherboard (MSI 845Ultra-ARU) was 1.65 volts, which caused some rebooting problems. If I did a soft reboot, it would sometimes not post afterward. I had to power off, wait a few seconds and then power back up. That is when I decided I would implement the "wire trick" to modify the default voltage to 1.85 volts.
First of all, I will give you the S-Specs and a few shots of the CPU itself, because you may not get the same results from another CPU. Your overclocking success will be dependant on your motherboard and RAM as well. This is the third 1.6A Northwood that I have overclocked, all were completely different S-Specs but they all pretty much performed the same. So I think it's safe to say that you will be able to hit 2.2Ghz no matter what. This particular CPU's specs are as follows:
- PROD CODE: BX80532PC1600DSL668
- MM#: 844085
- FPO/BATCH#: 3H215142W
- FAB: COSTA RICA
- PACK DATE: 04-11-02
Here is what you get in the box. Many people are hitting 800+Mhz overclocks using only the stock Intel heatsink and fan. When you take a look at these pics, you will understand why. This is by far the largest stock heatsink I have ever seen and at the same time, the smallest CPU I have ever seen. It's tiny, which makes doing the wire mod a bit difficult, especially for guys like me with big fingers and diminishing eyesight.
Just to give you a good idea of how small these things really are, I took a shot of the CPU next to a regular cheapo ballpoint pen and then a closeup of the pin grid with the tip of the pen in the picture for reference. After dealing with Pentium III's and Athlons for so long, it was a shock to see such a miniature processor.
Installing the CPU is as easy as it gets. You just drop the processor down into the 478 pin socket, and lock the latch down, pretty much like any other socket CPU. The heatsink assembly has 4 plastic clips that snap into the heatsink retention bracket on the motherboard. You lock 2 levers on the heatsink that puts pressure against the CPU, plug in the fan and you are done. Here is a screenshot of the Sisoft Sandra CPU benchmark at 2.4Ghz. I have the frontside bus speed set at 150Mhz at this point, and vcore at 1.65v.
As I mentioned earlier, the CPU ran fine at this speed but would fail to boot sometimes on a soft reboot. I could tell that this thing still had some more speed in it, and that I just needed a bit more juice to get me there. It was time for a voltage mod. By connecting 4 pins shown below on the pin grid array, you will trick the motherboard into setting the vcore voltage to 1.85v. I used a single strand of steel wire out of a piece of multi-strand speaker wire. There are probably better methods of doing this, but I didn't have any conductive grease handy, so I opted for the wire. It took me about 30 minutes to get the wire just right the first time because of those damned microscopic pins, but I finally got it. The 4 pins that need to be shorted are marked in red below:
Here is the finished mod. You have to look closely, but its there.
After the voltage mod was complete, the PC happily booted at 2.4Ghz. I rebooted several times to check for stablility and sure enough, the cold boot problem was gone! So, I decided to step the FSB speed up in 2Mhz increments (each 1 Mhz step=16Mhz increase for the CPU).
- FSB 152 - CPU 2432Mhz; no problem
- FSB 154 - CPU 2464Mhz; no problem
- FSB 156 - CPU 2496Mhz; no problem
- FSB 158 - CPU 2528Mhz; no problem
- FSB 160 - CPU 2560Mhz; boot into WindowsXP, then Physical Memory Dump.
- FSB 162 - CPU 2592Mhz; BSOD immediately after WindowsXP Logon screen.
I am pretty sure my PC2100 DDR memory is the problem at this point. The CPU temp isn't going over 100*F, so it's not a cooling issue. But, I did get an additional 132Mhz plus stablility from the voltage mod. Here is what I ended up with:
UPDATE! As I suspected, the memory was a limiting factor. I recently purchased some Kingston PC2700 ValueRam, which uses Samsung memory chips. This upgrade permitted me to achieve a stable 2.61Ghz with stock HSF. This is using a FSB speed of 163Mhz. This works out to 326Mhz data rate for the DDR, and 652Mhz for the CPU.
But, I ran into a bit of a problem I have never encountered before...
The CPU arithmetic ALU performance dropped! Yes, it actually lost performance with the speed increase!
The only thing I can think of that can account for the performance hit, is that I had to change the DDR memory timing from CL2 to CL2.5 in order to stabilize the system. I will continue playing with the RAM settings and see if I can't work it out, but if you know what else might be causing this, let me know!
Finally, most of you who have used SiSoft Sandra are familiar the the Performance Tips that Sandra offers to help you tweak your PC.
Here are the "Tips" that Sandra offered me!
Reduce FSB? Reduce memory bus speed? ReduceFSB/Memory multipier?
Maybe Sisoft should call it "How to not void your warranty" tips...
Warning: main(php/nav/footer.php) [function.main]: failed to open stream: No such file or directory in /home/pcx4010/public_html/p4oc.php on line 150
Warning: main(php/nav/footer.php) [function.main]: failed to open stream: No such file or directory in /home/pcx4010/public_html/p4oc.php on line 150
Warning: main() [function.include]: Failed opening 'php/nav/footer.php' for inclusion (include_path='.:/usr/lib/php:/usr/local/lib/php') in /home/pcx4010/public_html/p4oc.php on line 150