In a comment, you wrote

My plan is to use the money in my account to for the air ticket and the first month or so of my stay in Ireland, until my first paycheck comes in. I have checked the rent and other living expenses in Cork, and I believe USD 3000 should be enough for me to start with.

In that case, you have a cushion of 50% over your budget. I do not know about the cost of living in Cork, but for a month or so, this seems like an adequate amount to me. Let's look at the guide to supporting documentation:

Finances

 

• You must provide an up-to-date bank statement, showing what money has been paid into and out of the account over the last six months and showing sufficient funds to cover your costs.

 
• Bank statements must be on headed paper - internet printouts will not be accepted.

 
• Your name, address, account number and account type must be visible on the statement. Any large lodgements must be explained.

 
• If you are sending a bank statement from a deposit/savings account, you must also include a letter from your bank confirming that you are allowed to withdraw money from that account.

The first bullet point addresses your question. There is no explicit balance requirement for the bank account. The proposition that USD 4,500 is adequate will be stronger if you have a realistic budget prepared that shows expected expenses of around USD 3,000.

The third bullet point is significant, since the source of the money in the account is a single large deposit. Explaining this deposit probably warrants consultation with an Irish immigration lawyer. At a minimum, you will probably need a formal written statement from the relative who loaned the money explaining the purpose for which it was loaned to you (i.e., to help you cover your expenses before your first paycheck) and when you are expected to pay it back.

It may also be necessary to include the lender's bank statements showing the outgoing transfer. These should probably also make it clear that the lender has come by the money legitimately. The question of whether to include the lender's bank statements is the main reason for my suggestion to talk to an Irish immigration lawyer.

In a comment, you wrote

My plan is to use the money in my account to for the air ticket and the first month or so of my stay in Ireland, until my first paycheck comes in. I have checked the rent and other living expenses in Cork, and I believe USD 3000 should be enough for me to start with.

In that case, you have a cushion of 50% over your budget. I do not know about the cost of living in Cork, but for a month or so, this seems like an adequate amount to me. Let's look at the guide to supporting documentation:

Finances

• You must provide an up-to-date bank statement, showing what money has been paid into and out of the account over the last six months and showing sufficient funds to cover your costs.

• Bank statements must be on headed paper - internet printouts will not be accepted.

• Your name, address, account number and account type must be visible on the statement. Any large lodgements must be explained.

• If you are sending a bank statement from a deposit/savings account, you must also include a letter from your bank confirming that you are allowed to withdraw money from that account.

The first bullet point addresses your question. There is no explicit balance requirement for the bank account. The proposition that USD 4,500 is adequate will be stronger if you have a realistic budget prepared that shows expected expenses of around USD 3,000.

The third bullet point is significant, since the source of the money in the account is a single large deposit. Explaining this deposit probably warrants consultation with an Irish immigration lawyer. At a minimum, you will probably need a formal written statement from the relative who loaned the money explaining the purpose for which it was loaned to you (i.e., to help you cover your expenses before your first paycheck) and when you are expected to pay it back.

It may also be necessary to include the lender's bank statements showing the outgoing transfer. These should probably also make it clear that the lender has come by the money legitimately. The question of whether to include the lender's bank statements is the main reason for my suggestion to talk to an Irish immigration lawyer.