Confused: P4 CPU and ram....

yoda

yoda

yoda

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at the mo I'm running a P4 1.7GHz 400mhz FSB in an epox EP-4PLAI and 512mb PC 3200 ram...
Except... bios reports DDR400 @ 133 ?????

Also, I go a P4 2.7ghz 533mhz FSB which refuses to boot ????

now, looking at ram, DDR533 (PC4200) seems to be DDR2 ??????

Can someone shead any light on whats going on coz this P4 has confused me?

Thanks
 
the second P4 is LGA775 for sure. They made the socket change and ram change a bit back.

The older P4 is probably a 423 pin CPU, known as Williamette.

Bump the ram on the old one up as necessary.
 
nope, both are same socket....
cpu markins as follows....
6.66ghz /512/533
sl6pe costa rica
3348a372
 
yoda said:
nope, both are same socket....
cpu markins as follows....
6.66ghz /512/533
sl6pe costa rica
3348a372
Click to expand...

I want one of those. :D


You may need a BIOS update to support thea other cpu, also your board may not support 533FSB cpus, what board is it? As for the RAM, anything over PC2100 for 533fsb cpus will do. Don't get confused by RAM speeds, the 533fsb is just 133x4, currently your cpu (1.7) is running at 400fsb (100x4) while your RAM is at 533 i.e 133x4 quad pumped, any PC3200 RAM will run fine with either cpu, the RAM speed would be reduced however, getting PC4200 would only be a waste. From your post it would seem yor board is where the issue lies, as to if it can support the other cpu, your RAM is fine.

[edit] looking at your board specs it should support the cpu fine, is the cpu verified working?

BTW stabhappy, theres a lot of socket 478 wiliamettes too before Northwood came out.
 
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Your P4 1.7Ghz can either be Northwood or Williamatte. The effective FSB is 400Mhz which is quad-pumped from the actual 100Mhz so by default your RAM should be running at 100Mhz (DDR200 PC1600), however yours has been default to 133Mhz (DDR266 PC2100) probably because that is the lowest your DDR400 PC3200 RAM will support.

As suggested look into BIOS and see if there is a mem divider option which allows you to run your RAM at its native speed of DDR400.

That 2.66Ghz maybe the latest Prescott P4 and thus you may need to update your BIOS before it can work properly.

DDR533 can either be DDR2 or DDR1.
 
2660/512/533, Thats a northwood CPU, 512 is the cache size, and its a clear giveaway. To be more accurate its a Northwood 'B'. (Unless its a Prescott Celeron)

Was the computer working and then stopped, perhaps you can give a bit more detail on this computers history.

The 1.7Ghz will be a willimotte CPU (256k cache right?), as you say they both have the same socket that would make it a socket 478.

In reference to the first computer, if your running the memory in 'single' channel then the ram needs to be at 200mhz (DDR400) to match the CPU's 400FSB. If your running dual channel (two sticks and a compatible motherboard) then 100mhz or faster for the ram is fine. If your motherboard doesnt support single channel 200mhz ram (perhaps an old motherboard) then pick the fastest speed it supports.

I dont know if any socket 478 boards included a DDR2 memory controller, but certainly DDR1 was available as PC4000, and I think that some was made rated as PC4200. Certainly my OCZ ram ran happily at 266(DDR533).

Anyway, I'd try a battery out, bios reset and see if that gives any improvement to the 2.66Ghz computer. (Power off, ATX power leads removed from mobo, remove battery, use cmos clr jumper, wait 5 minutes, and then return everything to normal, and try to boot up).
 
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Corasik said:
In reference to the first computer, if your running the memory in 'single' channel then the ram needs to be at 200mhz (DDR400) to match the CPU's 400FSB. If your running dual channel (two sticks and a compatible motherboard) then 100mhz or faster for the ram is fine. If your motherboard doesnt support single channel 200mhz ram (perhaps an old motherboard) then pick the fastest speed it supports.

).
Click to expand...


Little correction, single and dual channel has nothing to do with MHz speed, its simple doubling the bus from 64 to 128 bit. And for his 400fsb he only needs PC1600 or DDR200 at minumum, for the 533fsb he needs PC2100 or DDR266 at minimum whether in single or dual channel mode. And yes, the 1.7 is a Williamette as the only Northwood cpus i know in 1.7Ghz flavour are mobiles.
 
Justintime said:
Little correction, single and dual channel has nothing to do with MHz speed, its simple doubling the bus from 64 to 128 bit. And for his 400fsb he only needs PC1600 or DDR200 at minumum, for the 533fsb he needs PC2100 or DDR266 at minimum whether in single or dual channel mode. And yes, the 1.7 is a Williamette as the only Northwood cpus i know in 1.7Ghz flavour are mobiles.
Click to expand...

Thats only half the story. If he uses DDR 200 on a single channel "64 bit" memory interface, then his P4 will be starved as it has a 64bit 100mhz 'Quad pumped' interface which is equivilent to the data transfer of DDR400.

So if his motherboard only supports single channel then PC3200 is required for optimal performance, just as I said. Slower memory will work, but it will bottleneck the processor.

If his board supports dual channel then the lower specification PC1600 is sufficient as 128bits x 200mhz is exactly the same bandwidth as 64bits x 400mhz.

Single or dual channel doesnt matter, but for performance its important to make sure that the memory interface is as high performance as the processors fsb. I stand by my original post.
 
I know thats how dual channel came about, to basically use slower memory that was more available than faster higher priced memory and give it a bit of a boost but i've honestly not seen much if any improvement over faster RAM vs Dual channel and the PIV bus isn't 100% efficient with the quad pump to actually saturate slower dual channel memory imo, especially on those older chipsets.
 
Well, regardless, According to the 'online' manual, that particular Epox Motherboard only supports a 64bit 'Single' channel anyway, and apparently it will set the memory speed to DDR266 for a 400FSB P4, 333 for a 533FSB P4, and 400 for a 800FSB P4.

So nothing to do except leave it as it is.
 
on a side note.... I got a 25% overclock outa this 1.7ghz P4.... yeh, ok it's on water and doesn't get above 25C at full load.... oh, and it stable... was playing C&C generals with zero hour all last night....

History to this PC...

my original PC, barton 2800 got dropped by a m8 when leaving his house after a LAN party... KO'd everything as it went bump bump bump down 15 concret stairs... bye bye a grands worth of PC...
since my m8 is a poor student and doesn't have two pennies to rub he can't pay me back... since I got made redundant the I don't have much cash ether...

The PC as it is now, has been put together from bits baught off ebay... except RAM, HD, DVD-RW and ATI Radeon 9550 and OCUK's Xblade case.

The PC at the mo is fully working... 25% overclock and fully stable...

The CPU it is running now is a P4 1.7 400/256/1.7 (non celly) currently running at 2.12ghz (125X17) Mem: DDR400 @ 166, FSB: 500MHz AGP and PCI clocks are both above normal. Could set them back to 66/33 but if I can get away with the extra speed, then why not...
The mobo auto adjusts the mem speed for me....

The new CPU was listed as working on Ebay... no pent pins...
when I insert the CPU and turn PC on, motherboard just beeps, beep, beep, beep, beep, beep... ect no POST type code to the beeps...
I'm guessing it cant get the bus speeds right...
I tried CMOS reset....

Only thing left is flashin the bios...

:edit
also, the 1.7 is a non HT processor.... or atleast, it only shows up as one under XP and linux.... the new one I think is HT....

and whats the quad pumping?????? - don't normally do intel crap...

And the PC only cost me £150 so far...
 
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oky, I got the 2.66 working.... only disapointment is it not HT.... :(

However, having said that.... it rips through compiling Linux From Scratch (LFS 6.1.1)... so, I'm happy, for now....

Had to back off the memory timings.... they running default at the mo... will play with them later....

Thanks for the help guys... love yas... lol
 
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