Maximum CPU Processor Upgrade for Dell Dimension 4300 / 4300S

Thursday, January 03rd, 2008
Last Updated:
Friday, August 17th, 2012

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I have a friend who owns a Dell Dimension 4300. It originally came with a Pentium 4 1.7GHz processor and after running across a few faster processors, I decided to try upgrading the CPU on the Dimension 4300. I did a bit of research and found a forum that mentioned the maximum CPU speed was a theoretical 2.0GHz for the system. So, I stuck in a 2GHz and it worked flawlessly. I also had a 2.4GHz Celeron that we yanked out of one of his newer computers and stuck that in just to see what it would do. It worked flawlessly as well.

I got to looking at the processor specs between the two and noticed that the FSB on the two processors was 400MHz. I also had a 2.60GHz with a 533MHz FSB and it did NOT work in the system. (I realize there is more to the correlation between the FSB and motherboard but I didn't feel like researching it too extensively. It's more fun to "plug it in and see what happens".)

So, I have decided that the Maximum processor speed for a Dell Dimension 4300 is going to be the highest processor with a 400MHz Front Side Bus. Like I said earlier, I used a 2.4GHz Intel Pentium 4 Celeron. BUT, I don't see why a full blown 2.4GHz Pentium 4 with a 400MHz FSB wouldn't work in the same system. I highly doubt there are any 2.6GHz processors with a 400MHz FSB, but in theory, if there is one, it will most likely work fine in the Dimension 4300.

Update: 2008-12-02
After reading through a comment below, someone mentioned that they were able to get a 2.8GHz 400MHz FSB Celeron to work without a problem. So, a 2.8GHz P4 should run just fine on a Dimension 4300. I also ran across the Intel Pentium 4 Processor Finder which allows you to filter the list of P4's based on various criteria such as the FSB. I was hoping to find a 2.8GHz P4 with a 1MB cache but the highest 400 FSB P4 built was a 2.8GHz with the following specs:

sSpec#CPU SpeedProcessor #CoresBus SpeedMfg TechSteppingCache SizePackagePCG
SL7EY2.80 GHzN/A1400 MHz0.13 micronD1512 KB478 pinN/A

Update 2010-05-09
Several folks have posted in the comments that a full P4, SL7EY WILL work in the 4300 as well as the Dimension 4300S! In order to accomplish this though, you MUST first update the BIOS to version A06 which will work for both the Dimension 4300 and 4300S.

Update: 2010-05-17
I had a brain fart idea and decided to post the Dimension 4300 Specs... Why I didn't do this before, I don't know. The processor info is kinda useless at this point given the tested info in the comments, but some of the other stuff might be note-worthy.

Dimension 4300 / 4300S Recap:
Maximum Known Working Upgradeable CPU: 2.8GHz Pentium 4 with 400MHz FSB known as SL7EY OR Any socket 478 processor with a 400MHz FSB.

I hope that answers any questions regarding the maximum cpu speed that a Dell Dimension 4300 can be upgraded to! (Also, Thanks to everyone who has helped by posting their findings in the comments!)

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Well, the one thing I can recommend for a faster browser experience, is to use Google Chrome over IE or Firefox. On newer computers, the sluggishness of those browsers aren't as noticeable, but the older computer tend to choke getting things to load. Firefox 4 "might" be faster whenever it comes out of beta, but we won't really know until we see it. Since IE9 won't ever see XP (according to M$) that leaves you with some slim pickin's. Opera or Safari might be good to use too. I don't ever use them though to say if they work one way or the other.

The only other thing I can suggest, is the better video card. I think for the AGP slot, the Nvidia 7600 GTX is the highest card you can get, but they're hard to find. I never stayed up with ATI to know what's comparable...

Good luck to ya!

I found out, after trying to replace my original SL5VH (1.6GHZ/400MHZ/478 pin), that it appears that two more specifications are critical: the micron technology and the VID Voltage Range.

My SL5VH CPU is 0.13 micron and has a VID voltage range of 1.75V. I tried to replace it with a SL7EY (2.8GHZ/400MHZ/478 pin) that has 0.18 micron and a VID voltage range of 1.475V - 1.55V. I couldn't boot-up, the hard drive wasn't recognized.

Update the BIOS to A06 and it should work.

I installed an SL7EY and it works fine.

A client of mine is having boot/POST issues so I went searching for a BIOS update. The A06 revision lists the following among the enhancements:

1. Updated microcode and SMBIOS support for newer processors.
2. Prevented boot-up of system when detecting a 533 FSB CPU.

This hopefully will extend the life of your PC, especially if you consider a decent video card (Radeon HD 3650 or equivalent nVidia). I've yet to try a 533 bus chip, but I will at some point. Hopefully I can get my hands on a 1MB cache model.

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awesome post, I'm trying to upgrade my girlfriend's Dell Dimension 4300 so that it will play x264 720p with CoreAVC with no problems. I upgraded her 1.7 Willamette P4 to a 2.0 Northwood P4, it recognizes the larger Northwood cache just fine and runs at 2 ghz. I worried about the multiplier limit, but if the other commenter had no problems with a 2.8 ghz northwood celeron, there shouldn't be any problems with a 2.8 ghz northwood P4 (400mhz fsb of course). this page really helped me out!!

the 2.8 ghz celeron worked just fine, but it was actually slower than the 2.0 ghz P4 when decoding 720p x264. the reason, i'm guessing, is the 128KiB cache, instead of the 512 on the P4. maybe the 2.8 p4 would do it?

Quite frankly, the Celeron CPU's are not worth going with, unless you are building a computer for your mom who only does e-mail and an occasional web page lookup :p Ok, I'm being a bit facetious when I say they are that bad but still, anyone who has tried to do anything with some computing power, will agree that a Celeron just doesn't have what it takes.

In answer to your question, "Yes" I whole heartedly believe that the 2.8GHz P4 will work better for your situation than the Celeron.

I did some digging in hopes to see if there were any 2.8GHz with a 1MB cache, but from what I found the 2.8's are all 512KB :(

Intel P4 Processor Finder:

Hope that helps!

I did a quick swap of the processor from a p4 1.4 (original) to. P4 2.4 (spare parts!) and didn't have to do anything else. It really didn't seem to make much of a difference in performance though. Going to update the bios and see if that helps. Just wanted to share since it seems there are still a few of us out there that like to play with these things!

It says max 512Mb of RAM but I have 768 in mine no problem. I am putting a 2.4Ghz/512/400 in it tonight but I am first going to try a 2.8Ghz/1M/533 just for the fun of it. It looks from previous posts that Dell locked it out from booting with this cpu in the BIOS, but we'll see. Plenty of thermal paste, and a little time to help my sister-in-law keep her old PC working for her kids. I know 1.6Ghz up to 2.4Ghz will show a big improvement, and cleaning up XP and removing all the extra crap will also help.

i have a dell 4300 with a cpu of 1.6ghz with fsb 400mhz,i put in an intel celeron cpu running at 2.8ghz with fsb of 400mhz and it works fine.

Did you re flash the bios? What bios flash did you use?