How much Ramm?
- Thread starter newguy1
- Start date
That might be enough to push my recommendation to more than a gig. Your system will run much smoother if your recording/playing app can have the whole thing in core, rather than on disk. I'd consider 1.5 gig (three sticks of 512MB) if you expect 500+MB files. If you're just going to have a few that barely reach 500 meg, 1 gig should be OK.
Dual channel mode effectively creates one 128-bit memory path from 2 independent 64-bit memory channels, theoretically doubling the potential bandwidth. However, before anyone gets too excited, the real world performance differential is about 1-5%. This is more beneficial to gamers than it would ever be traders.
I'm sorry, I don't mean to confuse anyone or "opine incorrectly."
I was not saying that addressable memory is set by L2 cache, period or otherwise. What I was saying was that, as a practical matter, the maximum usuable memory is set by L2 cache, regardless of what the processor is capable of addressing.
If so, then the "absolutely correct" information that was already on the thread was rather misleading, because, though it was absolutely correct, it was almost absolutely irrelevant to the original question.
Still, based on your premptory rejection of my comment, I thought that I was remembering something wrong and had foolishly incurred the ire of those who know much more than I; but after checking with the authorities, I don't think so.
I will quote Scott Mueller: " One important thing to note is that most external cache controllers have a limitation on the amount of memory that can be cached. Often this limit can be quite low.... Most original Pentium class chipsets... can cache data only within the first 64MB of system RAM. If you add more memory that that, you will see a noticable slowdown in system performance because all data outside the first 64MB is never cached and is always accessed with all the wait state required by the slower DRAM. Depending on what software you use and where data is stored in memory, this can be significant. For example, 32-bit operating systems such as Windows load from the top down, so if you had 96MB of RAM, the operating system and applications would load directly into the upper 32MB (past 64MB), which is not cached. This results in a dramatic slowdown in overall system use. Removing the additional memory to bring the system total down to the cacheable limit of 64MB is the solution. In short, it is unwise to install more main RAM memory than your system (CPU or chipset) can cache.
"Chipsets made for the Pentium Pro/II and later processors did not control the L2 cache because it was moved into the processor instead. So, with the Pentium Pro/II and beyond, the processor sets the cacheability limits. The Pentium Pro and some of the earlier Pentium IIs can address up to 64GB but only cache up to 512MB. The later Pentium IIs and all Pentium III and Pentium 4 processors can cache up to 4GB. Most desktop chipsets for those processors allow only up to 1GB, 2GB, or 4GB or RAM anyway, making cacheability limits moot. All the server-oriented Xeon processors can cache up to 65GB. This is beyond the maximum RAM support of any of the chipsets.
"In any case, it is important not to install more memory than the cache controller can support. If you want to know the cacheability limit for your system, consult the chipset documentation if you have a Pentium class or older system (or any system with cache on the motherboard), or check the processor documentation if you have a Pentium II class or newer system (or any system with all the cache integrated into the CPU)." (Mueller, pp 463-464)
Somehow I think that arguing about the hard versus practical limits of L2 cache in a thread that starts out with RAMM [sic] spelled wrong and a pointless question like "How much do you guys have on your computers?" seems a bit out of place.
Why not just answer the original posters question and be done with it:
As to your second question, I've got 4GB of RAM in my computer.
As to the first, "how much ram can a pentium D actually use?" , the answer is more than you'll ever need.
Next question.
Why not just answer the original posters question and be done with it:
As to your second question, I've got 4GB of RAM in my computer.
As to the first, "how much ram can a pentium D actually use?" , the answer is more than you'll ever need.
Next question.
While it is 100% true that in much older systems (Pentium era) your comments take hold, remember sir, that his "original question" as you pointed out was in reference to the Pentium D which is not limited by the ancient problems that you have mentioned. In other words, he will not experience said problems and shouldn't focus on anything but the current facts in relation to his Pentium D....Since you are so fixated on providing succinct answers, should you have not just told him/her that with the Pentium D this is not an issue? So my friend, may I ask why your discussing much older chips is relevant to the orginal question? Also, you might explain how my discussing current mathematical and physical limits is irrelevant or worse yet, misleading?
Pentium D EMT-64 address limit 2^64 or 16 Exabytes assuming it is truly 64-bit addressing (relevant)
Pentium D EMT-64 physical memory limit 128GB (relevant)
Pentium D does not suffer from these <= Pentium-era issues (relevant)
"If so, then the "absolutely correct" information that was already on the thread was rather misleading, because, though it was absolutely correct, it was almost absolutely irrelevant to the original question."
Pentium D EMT-64 address limit 2^64 or 16 Exabytes assuming it is truly 64-bit addressing (relevant)
Pentium D EMT-64 physical memory limit 128GB (relevant)
Pentium D does not suffer from these <= Pentium-era issues (relevant)
"If so, then the "absolutely correct" information that was already on the thread was rather misleading, because, though it was absolutely correct, it was almost absolutely irrelevant to the original question."
Well, I also agree with winter that this sort of discussion doesn't help anything very much.
But there's something I would really like to know. Despite the fact that EM64T is theoretically capable of addressing 16 exabytes of memory, the Pentium D has a 2x1 Gb L2 cache. Is there something different about this processor such that it is not constrained by the cache with respect to how much memory it can use efficiently?
But there's something I would really like to know. Despite the fact that EM64T is theoretically capable of addressing 16 exabytes of memory, the Pentium D has a 2x1 Gb L2 cache. Is there something different about this processor such that it is not constrained by the cache with respect to how much memory it can use efficiently?
Kinda off topic and now kinda on topic:
Without having dug into any references yet... I ask: How is the p-D EMT64 different from the p-4 EMT64? Other than dbl L2 size (i've got 1meg), the other thing I wonder about is this so called (p4 emt's 64b) "emulation" and that amd64 kicks the p4emt's ass (actually it was the xeons.. no tests for p4??). If anyone's able to give a quick description... appreciated.
Without having dug into any references yet... I ask: How is the p-D EMT64 different from the p-4 EMT64? Other than dbl L2 size (i've got 1meg), the other thing I wonder about is this so called (p4 emt's 64b) "emulation" and that amd64 kicks the p4emt's ass (actually it was the xeons.. no tests for p4??). If anyone's able to give a quick description... appreciated.