2.4c v 2.8c oc

[thelanx]

How do these two compare in terms of oc capability?

 

[jagec]

the 2.4c has a greater OC capability in terms of "free MHz" that you get from OCing, but the 2.8c will end up at a higher clock by the end of the day.

say, 2.4c will go to about 3.3GHz,
and 2.8c will go to about 3.5GHz.

 

[thelanx]

Cool thanks, just wondering, since if the 2.4c could reach just as high as the 2.8c, then the 2.4c seems like a great deal. It still is, but there is a niche for the 2.8c it seems.

 

[jhurst]

The 2.4C might be the better deal, but still the 2.8 will always outperform it. My 2.8C overclocks to 3.6 (257FSB), whereas the 2.4C OC's to about ~3.2 (some ppl get a full GHZ). For just a few bucks more, I would recommend the 2.8.

 

[thelanx]

What about performance increases to to fsb increases? The 2.4 overclocked to 3.3 would be at a higher fsb than a 2.8 at 3.5 right?

 

[jhurst]

You are right, it is running at a higher FSB. But with the multiplier, you are still getting better performance out of the higher overall clock speed. If you get ahold of some DDR600, and run 1:1 with the 2.4C, you will have a higher memory bandwidth and your RAM could be faster b/c you can run at a higher FSB, but as for the CPU the 3.5 wins out.

 

[smahoney]

A lot of the 2.8C's - especially the M0 stepping chips will hit 3.5GHz with a 250MHz FSB. Running 5:4 mem ration with PC3200 memroy at tight timings is a very good deal and most of the 865 motherboards will run that high on the FSB. The 2.4C is a bit cheaper but only very highend motherboards will run 275MHz FSB stable and your mem ratio of 3:2 will be lower then PC3200 (183MHz) or if you go 5:4 you will need PC3500 memory to work well (220MHz). And a 2.4C at 275MHz is still only at 3.3GHz.

I run a 2.8C M0 stepping at 262MHz on an IC-7G motherboard. I also have PC4000 memory at CAS 2.5-4-4-7 timings. But you can go with a less expensive AI7 or other 865 based board and less expensive PC3200 memory and run faster with a 2.8C than a 2.4C and still pay a bit less money overall since I don't know of a chipset other than the 875 that will run 275MHz+ FSB to get a 2.4 above 3.3GHz.

 

[charloscarlies]

I had a 2.4 (m0) that would do nearly 300 fsb on my IC7. I didn't have good ram at the time, so I couldn't really take advantage of the high fsb speeds, but it still flew. I didn't have much problem at all hitting 275-280 fsb on stock voltages, and 1.6-1.65 is where I hit my max of around 300.

I say if you have good ram save some money and get the 2.4...otherwise go for a 2.8 with an 865 board because you probably won't get past 250-260 fsb anyways.

Both are great chips though.

 

[nealh]

ok I am confused I thought the 2.8E was a 800mhz chip and 2.8c was 533 mhz chip

which was supports HT???

 

[Pauli]

Originally posted by: nealh
ok I am confused I thought the 2.8E was a 800mhz chip and 2.8c was 533 mhz chip

which was supports HT???

Both support HT, both are 800Mhz.

2.8E is Prescott core 1MB L1 cache, 2.8C is Northwood core 512K L1 cache.

 

[nealh]

thanks..does any 533 mhz chip support HT with a high multiplier...like 18, 19..with good O/Cing potential

 

[jhurst]

P4's lock their multiplier.. You can only tweak the FSB. HT is something you can not change, you can either enable it or disable it if the chip/MB support it. There are 533 chips that support HT,...like the 3.06 for example.

 

[nealh]

I understand the P4's are locked that is why I prefer a higher multiplier for my 845 e board..I would like a HT capable chip as well..

thanks

 

[jagec]

I think the 3.06 is the only 533MHz chip that supports HT...it was the one that debuted the new technology, then the 800MHz chips ALL had it.

 

[smahoney]

Originally posted by: charloscarlies
I had a 2.4 (m0) that would do nearly 300 fsb on my IC7. I didn't have good ram at the time, so I couldn't really take advantage of the high fsb speeds, but it still flew. I didn't have much problem at all hitting 275-280 fsb on stock voltages, and 1.6-1.65 is where I hit my max of around 300.

I say if you have good ram save some money and get the 2.4...otherwise go for a 2.8 with an 865 board because you probably won't get past 250-260 fsb anyways.

Both are great chips though.

I think you missed my point - you save a few dollars on a 2.4 but have to spend more on a motherboard that will go 275+ FSB (Your IC7 is a case in point) and more on the memory if you are going to run at a 5:4 divider. Unless you go up to 300+ MHz FSB and run 3:2 with PC3200 memory, you are going to have less performance for MORE money then a 2.8 at 250 on an 865 platform with PC3200 at tight timings.

2.8@250 = 3.5GHz 5:4 (200MHz) PC3200 CAS 2
2.4@275 = 3.3GHz 5:4 (220MHz) PC3500 CAS 2 - need a good board.
2.4@300 = 3.6GHz 5:4 (240MHz) PC3700 CAS 2 if lucky or very good PC3500

A 2.4 at 300MHz needs a very good motherboard and a very good chip. 2.8 at 3.5 is a lot easier.

2.8 more than 2.4 ~$175 vs ~$165
865 less than 875 AI7 ~$100 vs IC7 ~$120
3200 less than 3500+ 1GB CAS 2 ~$260 vs ~$300

So you save $10 on the CPU but have to spend $60 dollars more on the motherboard and memory... Doesn't make much sense to me.

 

[Pauli]

I agree with smahoney - it doesn't make sense to go with a 2.4c instead of a 2.8c. The price difference is only about $10, plus you stress your FSB and NB by having to run them higher to achieve a similar overclock result. You'd have to be foolish to choose a 2.4c over a 2.8c right now.

 

[scottZX9R]

Nealh asked about 2.8e and 2.8c. In this article everyone is talking about Northwood chips. Can you do the same with the Prescott chips?