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UkGamer
03-11-2005, 02:03 PM
Yeah, i may be about to buy a new pc with an 'old' p4 in it .
ie Intel Pentium 4 Processor 550 with HT Technology (3.40GHz, 1MB L2 cache, 800MHz FSB)

i read in a magazine that the 'old' pentium 4's may have hidden extension and intel may tell users how to enable them when the 64bit OS's arrive

is this true or was the magazine (pcformat uk) fantasing

hockey man
03-11-2005, 02:33 PM
I have a dell 4700 p4 socket 755 i think, is that a "new" one or "old" one.

UkGamer
03-12-2005, 12:21 PM
by "new" i mean it is a series 5 64bit and i do not know if dell has started using these yet

i an not a nerd
03-12-2005, 12:36 PM
The 64 bit proccesing requires a 64 bit core, so I'd say that the magazine was making things up...

pop pop
03-12-2005, 12:42 PM
I doubt it but maybe. Look here (http://www.sheaiden.com/TechSpecs/Intel.html) and find your CPU and see. Alternatively, go to the Intel site and look it up.


NOTE:
(The site linked is Saphalline's)

saphalline
03-13-2005, 01:01 AM
i read in a magazine that the 'old' pentium 4's may have hidden extension and intel may tell users how to enable them when the 64bit OS's arrive

is this true or was the magazine (pcformat uk) fantasingThe Prescott core has EM64T built-in, but not all of the Prescott-based P4's have it turned on. This is exactly like HT in the original P4's - only the later versions had it turned on. The short answer is no, EM64T must be enabled on the core level, and you can only turn it on at the Fab plant during production.

The magazine was in fact telling the truth, but only the version of the truth available at the time. Intel's original plans were to turn on EM64T on all Prescott P4's and then initiate a BIOS function to actually use it later on, but this proved to be far too complex, so Intel had to dump those plans. I think a large part of it also was the simple fact that Intel wasn't going to trust anyone not to mess with EM64T before they officially enabled it. This seems to me to be a reasonable fear, since unauthorized use of EM64T could have resulted in some pretty serious problems!

UkGamer
03-13-2005, 04:26 PM
well thankyou for clearing that up for me, how do you guys know so much ?!

i would also like to correct my mistake in my second post before someone buys a 5 series thinking i can do 64bit which IT CANNOT, only the 6 series pentiums ( 6xx ) can do 64bit

saphalline
03-13-2005, 11:00 PM
The "E", "F", and "5x1" LGA 775 P4's do have EM64T enabled. But not all of them do, and certainly none of the Socket 478 Prescott's. Just choose carefully. ;)