Please help me choose

I don't know which processor is better. Im planning to get an Intel 2.8Ghz and overclock it to a 3.0Ghz or more. This is because the price between a 2.8Ghz and a 3.0Ghz is about rm230(my currency).

These are the 3 processors Im considering:
Pentium 4 2.8Ghz Proccessor number(520J)
Pentium 4 2.8Ghz Proccessor number(520)
Pentium 4 2.8Ghz Proccessor number(521)


Im not to sure about the 521 because it supports the Execute Disable Bit. Im worried that if I overclock it, it might down size the voltage to suit the programs and my pc would be unstable. But I do like it because of the 64bit technology. Same thing with the 520J.

1)Is there anything better than these processors for the same price?
2)How overclockable are these processors?

I prefer Intel over AMD because of the HT technology. Could anyone help?

I would pick the 520J or the 521 of those 3 choices. The 520J would be the newer E0 stepping with Execute Disable Bit. The 521 is the only one listed that is 64-bit compatible if that's important (but there is no 64-bit software to speak of yet). I don't know how prices are for the 620, but that would really be my choice if you can find one for about the same price. The 620 will have twice the cache and will also support 64-bit. All of these should O/C pretty well if you have decent cooling. You should be able to easily hit 3.4 to 3.8 gig, maybe more with exceptional cooling and higher voltages.

Thanks for the reply.

But how exactly does that execute disable bit work? From what I read it says that the CPU will lower voltages according to the programs that require less stress. Will this affect stability when overclocking?

Also could you explain what advantages the E0 stepping has over the old stepping?

Im going to do some price shopping next week. Im planning to go for water cooling as Ive never had one. So yeah, some good cooling there.

Rickster said:

But how exactly does that execute disable bit work? From what I read it says that the CPU will lower voltages according to the programs that require less stress. Will this affect stability when overclocking?

Click to expand...

EDB is when a program is causing a certain type of memory overflow, the processor will stop the thread from accessing memory space. Has some security advantages.

See also http://en.wikipedia.org/wiki/NX_bit

From my personal experience, execute disable bit doesn't hurt overclocking. As for stepping revisions, each time Intel makes some changes and improvements, they release a new stepping. The newer the stepping, generally, the better the yield (which means slightly better overclocking for us). The Prescotts were released as B0 stepping and then about 5 months later they released the D0 stepping. Later they released the E0 stepping which is better yet. I've seen a lot of E0 steppings hit 4+ gig with watercooling. All of the 6XX series and anything with a "J" will be E0 stepping. The plain 520 might be any stepping depending on how long it was sitting on a shelf in some retailer's inventory.

Thanks for the reply Batboy... But I still have one last question, a very small one. I was reading on another topic, and he was saying that his processor might be locked.
Is there anyway to know, when purchasing the processor, that it is locked? And if so how can I unlock it if I do buy a locked processor?

I forgot to add, I checked the Intel website and it doesn't have and Intel processor 620. It starts from 630. Also I might be thinking of getting the 6xx series because of the scheduled price drops, so I saw that they have the SpeedStep technology (is that like thermal control? or does it reduce the clock speeds according to the requirements of the programs running?). Will that affect overclocking? If so how can I disable that?

Hehehe, that's more than one question. All Intel production processors have a locked multiplier. That's not a problem because we overclock by raising FSB.

Looks like they dropped the 620 and will probably drop the 520 series too. I know Intel also plans to drop the 920.

Speedstep is a good thing. When your CPU is at idle, it will automatically drop the multiplier down to 14X (lower speed) to reduce heat. When you put a load on the CPU, it'll automatically go back up to the faster clock speed. Most overclocking motherboards (like Asus and Abit) have a way to disable this in the BIOS if you want. The real advantage to speedstep is that you can drop the multiplier from say 16X on a 640 to 14X if you want to run a higher FSB. Higher FSB means more performance.

lol... I edited the post.

It's not a big advantage having the SpeedStep, especially if I'm going watercooled.

Thanks dude