Psu won't boot my pc

[rustyredline]

hi can you help me?
I've just built a pc to play some fairly old games and some low spec new games i.e. pes 2010.
anyway i bought a qtec dual fan 400w psu, but it will not power up the mobo, i have used it to power up an older mobo and it was fine. It baffles me and I'm having to run the machine off a spare 300w psu but this causes draw issues in games that should run fine on my specs. The PSU i bought for it puts the green light on the mobo on but it will not switch on no post no fans. I can get it to start on a 250w mATX psu but not the 400w that was intended for this machine.
The mobo has 24pin power connector but the 400w psu only has 20pins whereas the 300w psu i use has the 24pins, so you would think this is the problem the qtec psu don't have enough pins. if so then why does it boot on the mATX 250w which also only has 20pins.
Thanks for listening

 

[Lmeow]

Apparently Qtec's not a very good brand, could just be the PSU's incapable of delivering enough power to the motherboard through the 20-pin connector, whereas on your older system it worked fine because it didn't need as much power possibly.

 

[rustyredline]

think i should just go for a new psu any suggestions based on my system specs, i don't OC and just run it from a mid range tower with 1 dvdrw, 1 hdd,
well should i go for a brand or would a 450w generic psu be okay cheers

 

[Starges]

List your specs first

 

[rustyredline]

asus p5l mobo
2gb pc 5300 ram
p4 3.0ghz
geforce 7600gt
160gb maxtor hdd

 

[Lmeow]

Hmm. I'd go for a 400W Corsair or SeaSonic PSU, those brands are trustworthy, and their power supplies are of really good quality.

 

[Starges]

A good 450w psu will work for you. I'ld go with Corsair or Seasonic. They may be a bit on the high $$ side, but they are worth it.

 

[Starges]

Ohh.. didn't see your post Lmeow. 400w is also good

 

[rustyredline]

ok thanks for the suggestions, next stop ebay

 

[Onus]

Seasonic has some cheap (<$42) 80+ bronze PSUs in the 300W-350W range on Newegg. They don't have PCIE power cables, but you don't need one.

 

[JohnnyLucky]

Corsair and Seasonic are two brands that have a reputation for high quality power supplies that consistently earn high marks in technical reviews. They are reliable, stable, and come with a 5 year warranty. Lately we've been seeing a few other brands offering some high quality units. One example would be the Antec Earthwatts and the Antec TruePower New models which are a major improvement over Antec’s older psu’s like the Basiq models.

 

[rustyredline]

im at work all week so i will pick one up this weekend i was looking at a 460watt gigabyte psu i know they do good boards so i imagine their psu's would be ok. is it ok to put links on? still quite new

 

[Onus]

Yes, you can post links. If the Gigabyte has a little voltage switch on it, pass. Modern designs all have full range active PFC, and do not require a voltage switch.

 

[rustyredline]

no it has no voltage switch heres the link to the product i had in mind, will it be sufficient for my specs and still sufficient if i upgraded cpu to a intel core 2 extreme which are supported by my mobo,

http://www.eclipsecomputers.com/product.aspx?code=PSG-460SUP

 

[obsidian86]

i dunno that 460watts is made by fsp they been on the down side lately

would rather get this

http://www.ebuyer.com/product/150985

 

[jsc]

no it has no voltage switch heres the link to the product i had in mind,
http://www.eclipsecomputers.com/product.aspx?code=PSG-460SUP

It's a 220 volt only model. It has to have some sort of PFC to be sold in Europe. And if it had active PFC,I think the ad would say so. The ad also gives no power specifications. For me , that's an automatic downcheck.

obsidian is right. The 400 watt Corsair is a better choice, and it probably has more usable power with its 30 amp 12 volt rail.

I think that the 400CX is one of the best under 500 watt PSU's around. It's worth the extra price.

Our standard checklist and troubleshooting thread:
http://www.tomshardware.com/forum/261145-31-read-posting-boot-problems

 

[Onus]

+1 @jsc and obsidian86. The page says the other has active PFC, but limited to 220V, makes me wonder. OTOH, I wouldn't worry at all about the Corsair..