fsb hypertransport confusion

psycher1 · Apr 5, 2013

http://img35.imageshack.us/img35/1257/htspeed1.png

Ok, I have no clue how to interpret what I'm learning about all this.
4 * 3990 = 15,960MHz which is obviously more than 2,100MHz.

I suddenly worried myself when I thought my motherboard was limiting my cpu, now I have no idea what to think about this. It should get a HT speed of 2,600Mhz, or 5.2G. I'm not finding either of those numbers anywhere.

I feel like there's something fundamental behind all this that I'm not understanding but I can't pick up on it by looking around the net. And yes I know I'm likely just the next in the group of 20 people that ask this here every day but I just can't get around to applying my questions to what I'm finding on other topics.

Also, is there anything that looks wrong about the setup I've got going on? Anything in particular show up as something I should change? I've got a pretty massive CPU cooler so I shouldn't need to worry too bad about that much, but I'd still like to be safe. The other speeds like HT ref and PCIe and such, and the voltages, I have no idea about those except "turning this up a bit couldn't hurt."
(In very small amounts of course. I know that much at least.)

bgunner · Apr 5, 2013

I'm not sure why you are multiplying 4*3990. The HT goes hand in hand with the FSB ( although AMD does not use the FSB letters any more). The HT will change as the FSB is increased. example 210 FSB = 2100 HT and 240 FSB = 2400 HT. Using this info to get the the 2600 HT you need to increase the FSB to 260. FSB 260 = 2600 HT. now increasing the FSB will increase the Ram speed also. because the rams speed is tied to HT by a multiplier Just like the the CPU is.

example 200 fsb * 17 CPU multiplier = 3400MHz But up the FSB to 210 * 17 = 3570MHz the same holds true to the ram just the motherboard sometimes says 800MHz 1066MHz 1333MHz and 1600MHz in stead of multiplier x2 x2.33 x3 x3.33 and so on

EDIT: in your pic provided, the FSB I mentioned is refered to (as AMD calls it now) HT ref. clock (MHz)

HT ref. clock speed * HT multiplier gets your HT speed. so like I mentioned HT ref. clock 210 * 10 = 2100MHz HT and HT ref. clock 233 * 10 = 2330 MHz HT.

psycher1 · Apr 5, 2013

I multiplied them because I have 4 cores processing data at that speed each.
Which to me means that my computer is processing data at roughly 15,960MHz. Then I start thinking, my HT only passes 2100 of that at a time. = serious bottleneck.

This is why I end up thinking I'm missing something fundamental about how this works. Either way, if it was only the 3990MHz that my cores are running at individually, that's still more than the HT link speed the program reports.

But there ARE no motherboards that go over 2600 anyway. What am I confusing here?

bgunner · Apr 5, 2013

psycher1 :

you can not figure your speed like that because the data is processed on one core not on all cores at the same time. 1 data bit goes to one core a different data bit will be sent to a different core. This break up of data speeds up the CPU's ability to work on the data.

Core speed has very little relation to HT. The major relation it has is clock speed. the higher the clock speed of the HT the higher the CPU speed is because of the CPU multiplier.

psycher1 · Apr 5, 2013

I know how cores work. See this is my problem, I end up coming through like I'm clueless.
They're working at the same time, each individual core processing data at the clock speed. Cumulative, that means it can process a freaking ton of data, but only coming from one place at a time unless the program allows.
But, this data needs to come from the RAM (or the CPU cache when it can) so you need a fast HT speed to prevent data bottleneck between RAM and CPU.

I don't know if my HT speed is fast enough to accommodate this data transfer. I see massive numbers in the core clock speeds but a smaller (in comparison) HT speed, so does that mean the Bus speed that links my CPU to my RAM is lacking?

If not, how do I know? And if it is, what do I need to do to fix it?

bgunner · Apr 5, 2013

there is no issue. Yes increasing the HT can gain speed but the chances that a major bottleneck will occur are slim. you would have to be feeding a massive amount of data at one time through system and have it be multi-threaded to have an issue.

I run AMD 965BE cpu @ 4.04 GHz and a a HT of 2310 MHz. I don't bottleneck and run fine. you are concerning your self over a slim possibility that in most cases will not happen.

Search

fsb hypertransport confusion

psycher1

Distinguished

bgunner

Judicious

psycher1

Distinguished

bgunner

Judicious

psycher1

Distinguished

bgunner

Judicious

TRENDING THREADS

Latest posts

Moderators online

Share this page