Do I need a new PSU?

Zoom123

Member
Sep 5, 2009
101
0
71
Hello,

My current system is a Core2Duo E6300 (1.86GHz overclocked to 2.8GHz), 2GB DDR2 RAM, 1 SSD, 2 HDD and a Radeon 5670. My PSU is a Thermaltake TR2-470W.

I am now planning to upgrade to a 2500K with 8GB RAM, and overclock it to about 4.5GHz.

I will keep the same video card (which doesn't need much power). Will I need a more powerful PSU?

I entered the numbers (including the overclocking) at http://www.extreme.outervision.com/PSUEngine and the Recommended PSU Wattage is 375. (with my current system it shows 335, so going from overclocked e6300 to overclocked i5 and adding more RAM adds only 40W)
 

lehtv

Elite Member
Dec 8, 2010
11,897
74
91
2500K @ 4.5 will use a few dozen W more than your current CPU, and since the 5670 uses only 60W, your whole system will be well under 300W if stressed to max (which practically never happens).

You will be fine with your current PSU, no problem at all.
EDIT: checking the specs - is it this one: http://www.thermaltakeusa.com/Product.aspx?S=1172&ID=1538#Tab1

Two 12V rails, 14A and 15A respectively. Not a lot... Expected much more, that's only ~300 of +12V output in total. If it was a single rail PSU, I wouldn't be worried at all, but since the CPU takes its power from one rail only (correct me if I'm wrong), a heavy overclock might stress that particular rail too much. hmm
 
Last edited:

Zoom123

Member
Sep 5, 2009
101
0
71
Thanks. Another PSU related issue is that my PSU only has a 4pin +12V Power connector, while most motherboards now require 8pin connectors.

I read somewhere that a 4pin connector can be used directly, and elsewhere that a basic 4pin to 8pin adapter can be used. Is any of this true?
 

lehtv

Elite Member
Dec 8, 2010
11,897
74
91
Sorry, had to edit that after actually checking your PSU specs

Thanks. Another PSU related issue is that my PSU only has a 4pin +12V Power connector, while most motherboards now require 8pin connectors.

That would probably be because of the rail design of that PSU.

I read somewhere that a 4pin connector can be used directly, and elsewhere that a basic 4pin to 8pin adapter can be used. Is any of this true?

I've used a 4-pin connector in a 4-pin header while leaving the other 4-pin header on the motherboard empty. (For almost 2 years with no issues, with the system in sig.)
 
Last edited:

Zoom123

Member
Sep 5, 2009
101
0
71
Thanks lehtv.

So should I keep my current PSU or change it? I would prefer not to spend the extra money if I don't need to, but I would hate it to have difficulty overclocking because of the PSU!

Would there be any way for me to know that an overclock fails because of the PSU and not because of something else?
 

Blain

Lifer
Oct 9, 1999
23,643
3
81
* How old is your Thermaltake PS?
* Has it been run behind a good quality surge protector or UPS since being in service?
 

Zoom123

Member
Sep 5, 2009
101
0
71
* How old is your Thermaltake PS?
* Has it been run behind a good quality surge protector or UPS since being in service?

It is about 3 years old. It is run behind a surge protector (belkin), but where I live we very rarely have any electricity problems.
 

lehtv

Elite Member
Dec 8, 2010
11,897
74
91
I would change the PSU, the +12v rail design doesn't seem to cut it. You can get a Corsair CX500V2 for $40 or an Antec 520C for $35 from newegg atm (after rebates), both are single-rail PSUs with over 400W on the +12V, which is pretty much optimal for your system (~50% load on the +12V). Even Corsair CX430V2 would be fine given the low-power GPU, it's just $25 after rebate (ridiculous price really). Single 336W +12V rail.
 
Last edited:

Zoom123

Member
Sep 5, 2009
101
0
71
Thanks. I have a Corsair CX430 (not V2) in another computer which runs Athlon II X2 260 (not overclocked) and a Radeon HD 6670.

Would it be better if I took the CX430 for the new i5 system and put the 470W supply in the Athlon system?

By the way, last time I was looking for a power supply I believe I remember reading that having multiple +12 rails was considered a good thing. Did something change?
 

theAnimal

Diamond Member
Mar 18, 2003
3,828
23
76
By the way, last time I was looking for a power supply I believe I remember reading that having multiple +12 rails was considered a good thing. Did something change?

Number of rails does not matter. Read the sticky.
 

lehtv

Elite Member
Dec 8, 2010
11,897
74
91
^ yeah. Single rail and multi rail are both good as long as it's a high quality unit that's powerful enough for the system that it's powering.
 

fffblackmage

Platinum Member
Dec 28, 2007
2,548
0
76
Thanks. Another PSU related issue is that my PSU only has a 4pin +12V Power connector, while most motherboards now require 8pin connectors.
I believe mobos use the 8pin design, because they support higher TDP CPUs.

I read somewhere that a 4pin connector can be used directly, and elsewhere that a basic 4pin to 8pin adapter can be used. Is any of this true?
Not sure if it always works, but I haven't encountered any problems using the 4-pin +12V power cable in a 8-pin EPS power connector.

^ yeah. Single rail and multi rail are both good as long as it's a high quality unit that's powerful enough for the system that it's powering.
Your previous posts would suggest that a multiple rail system is inferior.

Thanks. I have a Corsair CX430 (not V2) in another computer which runs Athlon II X2 260 (not overclocked) and a Radeon HD 6670.

Would it be better if I took the CX430 for the new i5 system and put the 470W supply in the Athlon system?
Hmmm... I think swapping the PSUs might be a good idea.

btw, what are you planning to do with this computer? If you're not going to be benefiting much from the overclocking, just don't do it, and you'll be sure the PSU won't be exploding.
 

lehtv

Elite Member
Dec 8, 2010
11,897
74
91
fffblackmage said:
Your previous posts would suggest that a multiple rail system is inferior.
No, my previous posts suggest that the OP's PSU has an inferior multi-rail design compared to the single-rail design of the PSUs I recommended. Nothing about whether multi-rail design is in principle better or worse is suggested.

lehtv said:
Two 12V rails, 14A and 15A respectively. Not a lot... Expected much more, that's only ~300 of +12V output in total. If it was a single rail PSU, I wouldn't be worried at all

Maybe I was unclear in the above part quoted... The Thermaltake PSU which is rated at 470W is only capable or around 300 watts of +12V load. That is very little for a 470W PSU, single-rail or multi-rail. If the 470W PSU was capable of, say, over 200W per +12V rail, then he'd be fine with that. But since it's not, he may run into problems by powering an overclocked CPU from one rail only. If, on the other hand, the PSU was single rail and only capable of 300W of +12V, he'd be fine since that'd be enough to power the CPU and GPU combined.

The thing about multi-rail PSUs is that the rails need to be specced for much higher output than what all the rails are capable of combined. That way, you don't run into problems where any one of those rails falls short.
 
Last edited: