When the P4 came out on the market a few years ago I of course ran out and got me a ready built system consisting of the 845 chipset, 400MHz FSB, 1.8 P4 to replace my beloved Pentium I. Big mistake, I know that now. And worse of all I'm now stuck with a system that runs only SDRAM (pc133 – w/Peak memory Bandwidth of only 1GB/sec, I have 512MB installed) Asus P4B mobo. The CPU runs @18 x 100MHz = 1.8 GHz. And the damned multiplier (BIOS) is locked at 18x and I can only modify the CPU frequency. This system runs SOLID, no doubt about it, it runs everything(ut2004,doom3,etc), still while obsessively playing HL2 this month (at 1024x768, everything on highest, plus 4x AA with a 9600Pro) I experienced just a bit of lag at times as well as some audio “hicups”, not to mention loading times of up to 3 min, (AMAZING game by the way! …stupid ending though). My question: I found online this CPU for a $100 bucks: P4|2400|478|Box|512Cache|533/800FSB|0,13µ|HT|Northwood (Which would now make my system run at 18 x 133MHz=2.4) FSB now 533MHz, right? …Or still 400? I know what you are thinking. “Just get a new mainboard stupid!” Well yes, the problem is that getting a new MOBO for my system would force me to buy new DDRAM and CPU, about $300+ total vs. only $100 for the new CPU. Is the new CPU worth it performance wise? Or will my mobo/pc133ram still bottleneck the APG and new CPU? How about another stick of RAM, would that help? Thanks in advance! Peace.

The p4 2.4 you are looking at wil run at 533fsb. Waht you need to make sure is that the board you have will cope with the 533FSB processor. Check the mobo manual for that. If your board cant handle the 533fsb dont waste your money, the 2400 will not run at 400FSB Hope that helps. But I do agree with your statement, just go and get a new board with DDR and 800fsb capability. Regards IF IT AINT BROKE, DONT FIX IT

Here's the manual: http://www.asus.com/pub/ASUS/mb/sock478/p4b/p4b-105.pdf The 1.8 comes in Willamette and Northwood flavors any you might just have a pretty good overclocker. One of the pages in the manual describes a 133/66/33Mhz setting that would make a 2.4 out of your 1.8. PC133 SDRAM won't have any trouble at 133Mhz and the AGP and PCI slots are running at stock speeds. All overclocking efforts yield different results but, if you can pull it off, you just saved a hundred bucks. lazyman runs a P4A 2.0 (Northwood core) at 3.2Ghz...that's quite an overclock. Skip

Hey Skip !! Happy new year !!! Long time no see !! You into the overclocking side of theing these days ??? Hope he gets it righ, otherwise snaffuuu and he will need new chip and perhaps other few bits and pieces. A p4 2 at 3.2 ????????????? I do beleive what you saying but WOOOO on what board ??? This I want know. Janos IF IT AINT BROKE, DONT FIX IT

Hi Janos, Thanks, Happy New Year to you too! I've been overclocking for a few years just to get a little extra out of a machine. His P4B is a pretty good motherboard with the option to overclock either with dip switches on the board or in bios. In the event of instability or lock up somewhere along the line, the clear cmos jumper should restore everything to defaults. I believe lazyman uses a MSI 6457 V2.0 motherboard with the P4A 2.0. If I'm correct, MSI calls the board a 645E Max. Last time he mentioned the rig, I think he was running it at 152 or 153Mhz...looks like he's up to about 160 now. Not too bad for a word processing/internet machine. Skip

Hi Skip As I suspected, that board didn't have 533 fsb capability. Your manual link confirmed what I thought. Providing I read the thing right. Going bit blind these days skip, to many monitors taking their toll. The next generation of that board was the p4b533 with the E series chipset. There is no way he can slot in the 2.4 again if memory serves the 2.4 was the first of the 533fsb chips. ( don't quote me that was a long time ago) I do know the p4b533 was one of the fastest p4 boards on the market, ( as far as i can remember ) I used a number of them, and they sold so darn quick by the time I realised just how good the thing was they were just about all gone. And the thing hardly ever went down in price, almost to the vary last one. Think ASUS knew something !!! I built a real nice rig for a bloke, as just a general usage comp, and i slotted in a 350W psu which was sort of new at the time, mated it with a GF4 MX440 card by Auriga which had Hynix memory chips on it. The guy still has it today, love's the thing so much that he even throws a white sheet over the thing when not in use. LOL I kid you not he really does. Janos IF IT AINT BROKE, DONT FIX IT

Thanks for the input guys! I had the P4B .pdf manual since I bought the system and read it many times over, but it still left me with some doubts like jumper-free mode vs. unlocking the multiplier and things like that. But it seems you can't unlock (lower) the 18x on these cpu's, what about manually on jumper mode? Well, right now my system is overclocked at a little over 2GHz with the original 1.8GHz willamette, very stable and cool 18x111MHZ (topped at 121MHz w/no voltage ajustment), but it makes little overall performance and benchmark difference. The asus BIOS does have an option to intall a 2.4 CPU and automatically sets itself to 18x133MHz, meaning the P4B 400FSB DOES in fact support 533FSB (maybe even more) but will the bus REALLY run at 133MHz x 4 is the question? And even though pc133 could theoreticaly run up to 150MHz MAX, the i845 chipset/pc133data transfer limitations are just horrible, almost P3 levels! damned Intel, check it out: click However there IS hope for this 2001 system: click I guess I'll stick with my system for years to come still (no need for a new one really) and get the 2.4B(533) or C(800) CPU since the price is finally right now, I can always stick it in another mobo later, seems to be a great overclocker too. Besides A buddy just sold me a kingston pc133/CL3/1024MB stick for $100, insane price! It seems that nobody wants pc133 anymore, man even DDRpc3200 only runs at 200MHz anyway. And CPU's (478 northwood) are backward compatible (FSB-wise), right? The worse that could happen is that it'll run underclocked, but it WILL boot up regardless, right? I'll keep you posted, thanks again. Peace.