• We’re currently investigating an issue related to the forum theme and styling that is impacting page layout and visual formatting. The problem has been identified, and we are actively working on a resolution. There is no impact to user data or functionality, this is strictly a front-end display issue. We’ll post an update once the fix has been deployed. Thanks for your patience while we get this sorted.

How can I tell what's limiting my FSB?

E

EpsiIon

Platinum Member
I have an Epox 8K7A motherboard, 1 x 256 MB of Crucial PC2100, and a Thunderbird 1.33 GHz @ 1.418 GHz. Unfortunately, the highest FSB I can see on this thing is around 135... Obviously, something's limiting my overclocking potential and I want to know what it is. I doubt it's temp because I run around 41 C with a CAK 38 and stock fan.

In my case, would you guess it's the MB, RAM, or Processor?

If you have any ideas, please let me know!

Thanks,
Epsilon
 
Sorry! 🙂 Should have told you in the first place.


Vcore.1.76
Vagp..1.53
3.3V...3.35
5V......4.78
12V..11.94

I think my RAM's set to +.1 V because I couldn't really OC at regular (and +.1 V is default for the 8K7A).

Let me know what you think.

Thanks,
Epsilon
 
Your 5.0V line is very low and will only get worse if you increase the Vcore to 1.85. Since this is a basic requirement you need to at least borrow a PSU with better regulation or quality. Without this stable power, you can never OC' your CPU beyond what you've already accomplished. As soon as you get a stable PSU, then you can start with the FSB and then raising the voltage up to it's max of 1.85. Then you can try lowering the multiplier and then raising the FSB again until it becomes unstable. Then you can choose which one is better for you. After reaching the highest stable overclocking speed, you need to try to raise the CAS of the memory in the bios to find out if you can raise it anymore.
 
I heard some PSU allows you to adjust voltages with some kind of knob inside.. i do't know.
(please don't open that thing yet, it could be fatal to open a PSU if you don't know waht you doing)
 


<< Your 5.0V line is very low and will only get worse if you increase the Vcore to 1.85. Since this is a basic requirement you need to at least borrow a PSU with better regulation or quality. Without this stable power, you can never OC' your CPU beyond what you've already accomplished. As soon as you get a stable PSU, then you can start with the FSB and then raising the voltage up to it's max of 1.85. Then you can try lowering the multiplier and then raising the FSB again until it becomes unstable. Then you can choose which one is better for you. After reaching the highest stable overclocking speed, you need to try to raise the CAS of the memory in the bios to find out if you can raise it anymore. >>



Well, I must say it's a bit disappointing to find out that my power supply isn't really up to snuff... After all, part of the reason I bought my Antec SX1040B was the power supply. It was (and still is) my understanding that Antec makes a very nice line of power supplies. Maybe 300 Watts just isn't enough anymore... 🙁

If I were to buy a new one, what would you recommend. It would need to be able to run my rig (see my signature) with some headroom for extra hard drives, RAM, a GeForce 3 (or 4 😉), and future CPU / MB upgrades. ... lol Ok, it woud need to be able to stand a next-generation system (hopefully).

Also, if I yanked my modem, how much might it help? At all? I hate to admit it, but I'm not well-versed in what each individual voltage means or how they work with each other...

Anyway, thanks a lot for your help.

Epsilon
 
There's no need to buy another PS. The antec is topnotch stuff. The low 5V is an issue with 8k7a's 2 phase power solution. It won't matter what PS you use, it'll still be a bit low. What you can do is open up your PS and adjust the pot to increase the 5V /12V line.

Still, I think you're just coming to the natural limit of your cpu. Have you lowered your multiplier yet? You can push it more if you go above 1.85Vcore which is one of 8k7a's key features.
 


<< There's no need to buy another PS. The antec is topnotch stuff. The low 5V is an issue with 8k7a's 2 phase power solution. It won't matter what PS you use, it'll still be a bit low. What you can do is open up your PS and adjust the pot to increase the 5V /12V line.

Still, I think you're just coming to the natural limit of your cpu. Have you lowered your multiplier yet? You can push it more if you go above 1.85Vcore which is one of 8k7a's key features. >>



How would I do that? :Q:Q 🙂 Don't worry, I know the thing can kill me, and I won't go inside it unless I know what I'm doing (which I don't). But even if it's purely theoretical knowledge, I'd like to know it. 🙂

I've already lowered the multiplier, and that does allow me to OC the FSB just a bit more (1 or 2 MHz) but the overall speed of the system is reduced. 1418 is the fastest stable speed I could get without messing with the Vcore. I've been reluctant to do that, but I just might.

Thanks a lot for your suggestion. I'm glad it appears that my PSU is adequate.

Epsilon


Oh, one more thing. I could actually run it at 1466 for a little while (just messing with the multiplier) and it appeared to be stable, but froze in applications like UT. So I think my CPU has a little headroom left. 🙂
 
Adjusting your pot (potentiometer).
Disclaimer: You'll kill yourself, don't do it.

Now, since you *really* wanna....I adjust pots all the time, it's a piece of cake on most supplies. I have *never* done this on a computer PSU, so bear that in mind.

You'll need a tiny flathead screwdriver and a voltage meter of some sort. If I was going to do it, here's what I would do...

Crack open PSU, look for any silkscreens indicating testpoints for voltages. If I'm really lucky, the pots will be labelled. If everything is labelled, fire the system up with the PSU cover off (there are other ways too). Then I'd hold my voltmeter on the 5V TP (testpoint). Now, I'd place the screwdriver into the pot slot and turn it slightly. Monitor voltage. Did it go up to where you'd like it? Mission accomplished, get the heck out of there. If it went down, turn the pot the other way.

If nothing was labelled, I'd start sticking the voltmeter on various tiny post or loopy things (usually indicates a testpoint). Once I found my 5v, I'd look for a pot nearby and begin tweaking it.

What does a pot look like? On my X-Ray equipment (and other various sundry devices) they are usually small red plastic squares with a white, circular flathead slot for adjustment in the center of them. Piece of cake.

Discharge a loaded capacitor (big, circular tower looking things) at your own risk. Don't go near 'em.
Note: I would definitely use two leads on my volt meter....one for testing the voltage and another to go to ground.

That's how I'd go about it, but this is no means a suggestion for you or others to begin modding your PSU's. 😉

I'd do it while the supply was *hot* but this is quite dangerous...and I've done it quite a bit on other types of both high voltage and low voltage supplies.

Enjoy the fireworks, wear rubber shoes.

-Wandere
 
Yeah, that's pretty involved. I don't think I'll be doing that any time soon. 🙂

Thanks for the information!

Epsilon
 
Can you adjust the pot when the PSU is turned off and compeletly discharged?
Like.. turn the thing in one way, and see how that made difference.. then turn it off..and discharge, then make another adjustment if needed?
 
You must log in or register to reply here.

TRENDING THREADS

Back
Top