What's this MT/s thing, guys look.

[walkerbowe]

Ok, so I'm surfing around the varies computer sites, and I'm looking at the different mobo's. Now suddenly I'm not seeing fsb's written anymore, but this new MT/s??? I go and check other sites and see the same MT/s thing. What this new rating, and how come there not listing the fsb anymore, or how do you convert this MT/s to fsb old school, please someone explain it.

Below is the specs of a mobo I was looking at, look it's got the MT/s thing.

Here's a link, so the site where I saw it, http://shop.ai-tech.com.au/A.i.TECH_...MTs__4DDR.html

Supported CPU: Socket 939 AMD Athlon 64FX/64
Chipset: NVIDIA nForce4 SLI
FSB: 2000 MT/s
RAM: 4x DIMM DualChannel DDR 333/400 Max 4GB
Slots: 2x PCI-E X16(SLI mode: x8,x8), 2x PCI-E X1, 3x PCI
Ports: 2x PS/2, 1x LPT, 10x USB2.0(Rear 4), 2x RJ45, 2x SPDIF out, 1x IEEE1394, Audio Ports
IDE: 2x ATA 133 with NV Raid 0/1/0+1
SATA: 4x SATA2 3.0Gb/s with NV Raid 0/1/0+1, 4x SATA with Raid 0/1/0+1/5 by SI3114R
Onboard Audio: Realtek ALC850 8-Ch
Onboard LAN: nForce4 built-in Gbit MAC, MARVELL GbitLAN
Onboard 1394: 2x 1394 ports
Form Factor: ATX

[Cafe_333]

MT/s meaning MegaTransfers per second refers to how many one million data transfers take place.
1MT = 1 million data transfers.

The way all CPUs communicated to the Northbridge and the ram, was through a parallel Front Side Bus. Then when the Athlon64 was introduced, AMD opted to use a new type of high speed bus to communicate with the NorthBridge called the 'HyperTransport' bus - a serial interface which allowed data transfer rates of 3.2GB/s (1600MT/s) in both directions, giving a total bandwidth of 6.4GB/s. Current AMD motherboards with newer revisions of the HyperTransport bus now allow total data transfer rates of 8.0GB/s (2000MT/s).

EDIT: In contrast btw, Intel P4 533fsb CPU's perform data throughputs of 4.2GB/s - and can not communicate in both directions simultaneously like AMD can. Finally, their flagship 800fsb CPU's perform at 6.4GB/s.

Block Diagram of a sample VIA chipset with the HyperTransport bus:
http://www.via.com.tw/en/images/prod...blkdiagram.jpg

[goofball]

MT/Sec = mega transfers/second.

technically, there is no FSB in Athlon64 systems, since the memory controller and traffic has been removed from the chipset. now, there is a point to point link (Hypertransport) from CPU to chipset.

[goofball]

In contrast btw, Intel P4 533fsb CPU's can only perform at a max data throughput of 3.97GB/s - and can not communicate in both directions simultaneously like AMD can. Finally, their flagship 800fsb CPU's all top out at 5.96GB/s.

how are you getting those numbers?

533 FSB max throughput = 133.33 x 4 x 8= 4.264GB/sec
800 FSB max throughput = 200 x 4 x 8 = 6.4GB/sec

unless my math and understanding is wrong. I'm not taking bus efficiency into effect, as I am calculating peak throughput.

[Cafe_333]

I remember reading about that on THG when Athlon64 was first introduced.
http://www.tomshardware.com/cpu/2003...lon_64-10.html
"By comparison, the Pentium 4 with 533 MHz FSB allows a maximum data throughput of 3.97 GB/s - but not in both directions simultaneously."

I grabbed the numbers from that, but yours does seem more accurate. I suspect mine may be off but i'll google some more.

EDIT: odd, not sure how THG got that figure, but everything else I've read on various sites from google support 533fsb @ 4.2GB/s and 800fsb @ 6.4GB/s. However those may be theoretical and the bus efficiency could be what THG was stating - though that was not made clear. Anyway, I corrected my above post.

[konfusion666]

all you need to know is that, generally speaking, a Socket 939 motherboard will give you 2000MT/s (because the HyperTransport bus is running at 1GHz).

and a Socket 754 motherboard will give you 1600MT/s (HT Bus runs at 800MHz).

anyways, that just assumes "stock" - if you overclock you can run them at whatever the hell you want. usually you don't need to OC the HTBus though, I don't think modern hardware/applications has come close to saturating it (excepting server stuff)

[walkerbowe]

all you need to know is that, generally speaking, a Socket 939 motherboard will give you 2000MT/s (because the HyperTransport bus is running at 1GHz).

and a Socket 754 motherboard will give you 1600MT/s (HT Bus runs at 800MHz).

anyways, that just assumes "stock" - if you overclock you can run them at whatever the hell you want. usually you don't need to OC the HTBus though, I don't think modern hardware/applications has come close to saturating it (excepting server stuff)

so if it has a 2000 MT/s then it's 1gz bus. I'm assuming whatever the MT/s is, half that and that's what the fsb is?

Is that a fair thought?

I ask all these questions, cause when your chooing DDR memory, you have to know what speed to buy, and since pc3200 runs at 400mhz. You have to decide what speed to buy, if your getting a newer board etc.

[konfusion666]

you don't need to concern yourself with anything.

just get PC3200 ("400mhz") memory unless you are planning on overclocking, then get good brand-name PC3200 (OCZ) or something rated higher (like PC4400... whatever).

most current Athlon64's and most Semprons are on PC3200, so that's all you need...

[Cafe_333]

so if it has a 2000 MT/s then it's 1gz bus. I'm assuming whatever the MT/s is, half that and that's what the fsb is? Is that a fair thought?

Sounds right to me. Considering AMD motherboards with 1600MT/s and Intel boards with 800FSB both give 6.4GB/s data throughput, that would be a fair *thought* at most, but keeping in mind HyperTransport is a serial interface - meaning it's point to point direct communication in both directions, while Intel is using a parallel FSB which communicates in one direction at a time. Remember, "technically, there is no FSB in Athlon64 systems" as goofball put it.

[walkerbowe]

you don't need to concern yourself with anything.

just get PC3200 ("400mhz") memory unless you are planning on overclocking, then get good brand-name PC3200 (OCZ) or something rated higher (like PC4400... whatever).

most current Athlon64's and most Semprons are on PC3200, so that's all you need...

so what's the speed of the bus from the memory (pc3200) to the cpu? If I was going to buy DDR OCZ memory or something to that match my system. How would I be able to tell what speed to buy, so that I don't buy faster memory then my MT/s thing whatever is, non-fsb stupid thing, grrrr.???

[walkerbowe]

you don't need to concern yourself with anything.

just get PC3200 ("400mhz") memory unless you are planning on overclocking, then get good brand-name PC3200 (OCZ) or something rated higher (like PC4400... whatever).

most current Athlon64's and most Semprons are on PC3200, so that's all you need...

I thought I wouldn't need to overclock? I would just need to buy faster memory, like say OCZ Platinum PC2-8000 (1ghz) ? Isn't buying memory that fast, actually the same speed as the serial bus MT/s 2000 rating? or is the memory slower or faster then the MT/s rating etc?

[Cafe_333]

so what's the speed of the bus from the memory (pc3200) to the cpu? If I was going to buy DDR OCZ memory or something to that match my system. How would I be able to tell what speed to buy, so that I don't buy faster memory then my MT/s thing whatever is, non-fsb stupid thing, grrrr.???

You match the data throughput of the bus speed. In the old days this was easy because with a FSB of 400MHz, you only need DDR400 ram. For Intel systems of 800FSB, you need two bars of DDR400 in dual channel to give 800MHz speeds.

With new AMD systems using the HyperTransport bus, you need to know what the MT/s is. The first Athlon64 boards were 1600MT/s, equivalent to 6.4GB/s. In this case, using two DDR400 modules in dual channel configuration will give you a bandwidth of 6.4GB/s (PC3200x2).

[Cafe_333]

I should point out a change from my previous post. Currently all Athlon64's only perform at 1600MT/s. Two bars of DDR400's in dual channel configuration will actually give you the most optimal performance.

The latest AMD boards now do 2000MT/s, equivalent to 8.0GB/s - which can support X2 processors that also perform at 2000MT/s. The closest ram to match these dual core cpus are two PC4200's (DDR533) in dual channel giving 8.4GB/s bandwidth (PC4200x2). However because of this, I do believe that current Socket939 motherboards are not ideal for dualcore CPUs because it is bottlenecked by the ram. Currently they only support max PC3200 (DDR400).

It is only ideal to buy Athlon64 cpus for the time being. By the time X2's come down in price, hopefully by then there will be AMD boards that can support DDR533 and up.

As an aside note.... if you think X2's are fast now, just wait and see how much more potential these bad boys have when DDR533 AMD boards hit the market.

[konfusion666]

yes, basically the point is you just use standard PC3200 DDR RAM with any consumer-grade Athlon64.

don't bother trying to figure out HyperTransport, bus speed, MT/s ... just get some PC3200 and be done with it.

I should point out a change from my previous post. Currently all Athlon64's only perform at 1600MT/s. Two bars of DDR400's in dual channel configuration will actually give you the most optimal performance.

you are just confusing the guy, plus you don't know the K8 architecture very well.

there is no relevance between the speed of the HyperTransport bus and the speed of memory.

once again, the K8 architecture does NOT use the HyperTransport bus to communicate with memory.

(don't worry, i've made the same mistake before)

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

[goofball]

just look at it this way.

without introducing any CPU memory dividers, you would want at least PC3200.

if you start to increase the HT frequency from the base 200, the memory speed will also increase

216 = PC3500
233 = PC3700
250 = PC4000
263 = PC4200

and so on.

while HT and memory speed do not have a direct relationship, the clock generators are somewhat linked. increasing the HT will increase the memory speed.

HTT is for communicating from CPU to chipset, not CPU to memory.