What is the FSB on a Sempron?

[Bullman]

I am looking for a new processor for a PC upgrade. I am looking at some of the AMD Semprons, and that is where my questions begin. The Sempron Socket 754 processors all say on the FSB: "Integrated into Chip". What exactly does that mean? I am trying to figure out what memory will match up with those Semprons. Here (http://www.newegg.com/app/ViewProduct.asp?catalog=343&DEPA=1&submit=property&mfrcode=0&propertycode=&propertycodevalue=6355) is a link to the Semprons.

Also, the Socket 754 Sempron Processor for the 2600+ shows a speed of 1.6GHZ, and the Socket A 2600+ shows a speed of 1.833GHZ. Why is that and which processor would be the better choice?

Last but not least. Is the Sempron Processor a better choice over the AthlonXP processors. I know the Socket A Athlon is the older version, but which will give me the best performance? I have done some searches for past threads on this, but I am still as confused as when I started. :D

[Paul Komski]

I quickly get confused when it comes to CPUs but I believe the fundamental difference is a change in the underlying architecture when moving from K7 to K8.

The socket 754's are also capable of supporting 64bit CPUs and Athlon is reported to be phasing out Socket A CPUs in the near future.

http://www.cpuid.com/K8/index.php

The hardware gurus around here will be able to be much more specific.

[pentachris]

The Sempron Socket 754 processors all say on the FSB: "Integrated into Chip". What exactly does that mean?
The memory controller is integrated into the chip; it doesn't go through the north bridge of the chipset. Don't ask me exactly what that means; it's just what I read (http://forums.amd.com/index.php?showtopic=11141).

[NeWbiE :-)]

saphalline explained it to me once but was farrr to confusing for me at the time mgiht be able to do a search on it on this forum

[jlreich]

Well, wait for Saph to confirm, but if I understand it correctly, "integrated into chip" means the it runs at the full clock speed of the CPU. Meaning that if the clock speed on the CPU is 1.6GHz, then that is the FSB speed. Also and again if I remember right, since it doesn't run through the chipset on the mobo, it is not technically a FSB, but a direct onboard memory controller.

I'm 99% sure about the first part. Maybe 75% sure about the last part. :rolleyes:

[saphalline]

AMD did a great but confusing thing with its K8 core! :p It put the memory controller onto the CPU die and integrated it into the core.

FSB stands for "front side bus" and is the connection between the CPU and the memory controller. So what happens when you merge them? You get a core-speed FSB and no Northbridge to go with the chipset! Technically, there's still an FSB, it's just a lot shorter now (in the sense of what defines a "bus"). Ok, ok, very confusing, I know, but trust me! Performance has gone up!

With the FSB and memory controller built into the CPU core, this leaves a lot of confusion on the consumer end. Basically, Socket 754 is best paired with single-channel DDR400 RAM, and Socket 939 is best paired with dual-channel DDR400 RAM. That's how the onboard memory controllers work with the rest of the system. This is something they don't tell you when shopping for a K8-based CPU, though!

Moving on, we see a great example of competing CPU architectures! The Socket A Sempron is based on the T-bred B core and so needs a CPU core speed of 1.83GHz to reach the rating of 2600+. Meanwhile, the K8-based Socket 754 Sempron achieves the same 2600+ rating with a core speed of only 1.6GHz and with half the L2 cache! :eek: How did that happen!? Well, the K8 architecture is so darn powerful that even with those handicaps it easily beats the pants off the older K7 CPU's. Part of it is the onboard memory controller (the 754 Sempron has more RAM bandwidth, too) and part of it is the raw horsepower behind K8 (of which I won't go into too many details here!). For more proof, take a look at the Socket 754 Sempron 2800+, which runs at the same 1.6GHz core speed except it has 256KB of L2 cache. More L2 cache is the only difference between the 2600+ and the 2800+. All it needs is more cache, and it gets a higher rating! Talk about raw IPC and cache hit percentage!! :D It's the same with the 3000+ and the 3100+, just more cache.

[Paul Komski]

mmmm - saphalline.

It all reads as nice as a good novel.

;)

[jlreich]

Thanks Saphalline. I knew that last part didn't sound just right. :)

[Bullman]

Ok, things are making a little more sense to me now. :D What it looks like to me is the Sempron is a newer and better CPU compared to the Athlon XP. They are still about the same price range as each other so Sempron would be the best price/performance (and upgradeable) choice.

Basically, Socket 754 is best paired with single-channel DDR400 RAM, and Socket 939 is best paired with dual-channel DDR400 RAM.

So how much performance would I be losing if I used DDR333 PC2700 RAM? I am asking since I was planning on using two sticks that I have. I am just trying to upgrade a system using some newer parts, and using some older parts I already have.

One other thing. How does the Celeron D @ around the 2.4, 2.6ghz range stack up against the Sempron 2600+ and the 2800+?

[saphalline]

So how much performance would I be losing if I used DDR333 PC2700 RAM?Ummm... not a whole lot actually. I estimate about 7-11% loss during max CPU usage, but for less intense apps, it would be more like 0-2% loss. AMD's CPU's are notorious for not being as bandwidth hungry as Intel's CPU's. Plus, the onboard memory controller significantly reduces latencies between main system memory and L2 cache, so a 754 Sempron paired with DDR333 is just as good as an AthlonXP Barton paired with DDR400.

I personally think we'll all see amazing results when an onboard memory controller uses dual-channel DDR2! Now I'm just wondering whether AMD or Intel will be the first to breach this milestone...

One other thing. How does the Celeron D @ around the 2.4, 2.6ghz range stack up against the Sempron 2600+ and the 2800+?A one-on-one deathmatch? Let's see... a Celeron D 335 (2.8GHz) vs a 754 Sempron 2800+ (1.6GHz). Hmmm... not much of a deathmatch! The Sempron is going to dominate! The difference is in the way that Intel and AMD cripple their main CPU designs to get down to the value CPU's. Quite frankly, Intel does a lot more crippling than AMD! The Sempron lacks 64-bit capability (for now) and some of them have less L2 cache than the A64's, but other than that, there's no less RAM bandwidth vs the 754 A64's and no other differences. Intel's Celeron D, on the other hand, has less RAM bandwidth (533 vs 800 FSB), 1/4th the L2 cache, and no hyper-threading. That's a lot of trimming! With all those things against the Celeron D, it just can't keep up with a Sempron. Add those back into the mix, however, and the flagship P4's are certainly up for a fight with the A64's! Just goes to show that Intel does not want the Celeron D infringing on P4 land!

Overall, though, I have to say that a deathmatch between the value CPU's is pretty moot. Whether you're looking at a Celeron D or a Sempron to save some money, either one has more than enough power for all but the most demanding tasks. The slowest Celeron D is still well over 2GHz, and Sempron's are higher still. My min recommendation for good real-time video editing is a 2GHz CPU, so just about any average user is going to be very pleased with the latest "value" CPU's! Of course more RAM for those value PC's is always nice, but no one buying a new PC is going to be wanting for CPU power! This has been true for at least the last 2-3 years, but now the video editing mark has been shattered, there's no going back! I shake my head in wonder knowing that in another 12-18 months, we're all going to be talking about dual-core 2.8GHz Celeron's as the new value CPU's. And by that time, I doubt Intel will leave EM64T out of the loop! The sheer amount of power we all have at our disposal...

[Bullman]

Thanks for all the Info Saphalline and everyone else. I just ordered the parts from newegg to do the upgrade. Here they are.

AMD Sempron 2800+ (http://www.newegg.com/app/viewProductDesc.asp?description=19-104-224&depa=0)

Asus K8S-MX Mobo (http://www.newegg.com/app/ViewProductDesc.asp?description=13-131-518&depa=1)

Mushkin 184 Pin 512MB DDR PC-3200 (http://www.newegg.com/app/viewproductdesc.asp?description=20-146-219&DEPA=0) Times 3 (2 for my sons PC, had to do it at that price.)

ENERMAX 270W Power supply (http://www.newegg.com/app/ViewProductDesc.asp?description=17-103-453&depa=0) +12 Rail @ 20A

Wish me luck! I am sure I will be here at the mid/end of next week asking some more questions.

[joea64]

Let's not forget, in light of what Saphalline and others have said, that a "value" CPU today has as much power as a high-end CPU did two or three years ago. My own new setup has a Socket 754 Sempron 2800+ paired with 1 GB of Super Talent PC3200/DDR400 operating at a latency of 2.5 and an ATI Radeon 9550 with 256 MB RAM. It is left as an exercise for the reader to determine just how powerful this system is, but I will match it against my former main system (an Athlon XP 2000+ with 512 MB of Crucial PC133 SDRAM and ATI Radeon 9000 with 128 MB) any day of the week and twice on Sundays.

[joea64]

Thanks for all the Info Saphalline and everyone else. I just ordered the parts from newegg to do the upgrade. Here they are.

AMD Sempron 2800+ (http://www.newegg.com/app/viewProductDesc.asp?description=19-104-224&depa=0)

Asus K8S-MX Mobo (http://www.newegg.com/app/ViewProductDesc.asp?description=13-131-518&depa=1)

Mushkin 184 Pin 512MB DDR PC-3200 (http://www.newegg.com/app/viewproductdesc.asp?description=20-146-219&DEPA=0) Times 3 (2 for my sons PC, had to do it at that price.)

ENERMAX 270W Power supply (http://www.newegg.com/app/ViewProductDesc.asp?description=17-103-453&depa=0) +12 Rail @ 20A

Wish me luck! I am sure I will be here at the mid/end of next week asking some more questions.

If you want to know what I think, get yourself an Antec TruePower 430W or 480W instead of that Enermax; that kind of setup really requires at least 400W especially if you're going to run more than one hard drive/optical drive. Your son and your son's computer will thank you, and EWiz has the 480W for $90 including shipping, or did when I ordered it last month.

-Joe-

[jlreich]

Mushkin 184 Pin 512MB DDR PC-3200 (http://www.newegg.com/app/viewproductdesc.asp?description=20-146-219&DEPA=0) Times 3 (2 for my sons PC, had to do it at that price.)
You bet! It's amazing how ram prices have dropped so quick. I bought two of those last Christmas for my kids computer, and payed $67 a piece for them. And I thought that was a pretty good deal at the time. Now they are on sale for $42.55!! And free shipping. :eek:

I have to agree with joea64, 270W seems a little low, even though the 12v+ rail is good.

Happy building. :)

[Bullman]

Well, I did alot of searching over the net for good mATX power supplies, and even if I did find over 300 watts it was nothing you would want to put into a system. Most of them are never heard of before brands and have around 10A or so on the 12v rail. I really like Enermax PSU's and it was the best one I could find that would fit in my system.

The only other parts that will be in the system are what are already in there running off of a 150watt PSU. There will be one HDD and one optical drive. There doesn't seem to be a whole lot of choices for mATX. Thanks for the comments though, I wish I could have found a larger PSU with the same quality that the one I chose has. :D

[saphalline]

I think everyone missed the fact that it was a microATX PSU. :p Didn't the odd-looking pic tip you guys off? You ever see an ATX PSU with an external fan like that?

[jlreich]

That's right, I forgot it is a microATX. I was even asking Bullman about that on the other thread. :o Completely slipped my mind.

[Bullman]

Well, an update on my progress. I recieved all items on Wednesday and began the upgrade. Everything went fairly well, once I found out that the Mushkin Ram would not work in slot 1 in this board. I tried a single stick of Kingston (same speed and size) in slot 1 and it worked great. I then added the Mushkin Ram into the second slot and it also worked. The other two sticks didn't work in my sons Gigabyte board either, but they work great in my Dell system. :rolleyes: I am going to do more trouble shooting on that. Anyway, back to the update. Everything fit fine into the HP case and my mods to the Power button, power led, and HDD led worked great, it looks like factory work. :cool: I have got WinXP home SP2 installed and working great except for one problem in this new thread. (http://www.pcguide.com/vb/showthread.php?p=227043#post227043)

I just wanted to say thanks to everyone for your input. I always wanted to know if HP's were upgradeable, and now I know. :D